moved source directories into `/src` (#264)

* moved source directories into `/src`
* updated bundle.lua for new `src` path
* moved some docs, icon
* removed old test trees

6 files changed, 7946 insertions, 0 deletions

diff --git a/src/zenserver/cache/cachetracking.cpp b/src/zenserver/cache/cachetracking.cpp
new file mode 100644
index 000000000..9119e3122
--- /dev/null
+++ b/src/zenserver/cache/cachetracking.cpp
@@ -0,0 +1,376 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include "cachetracking.h"
+
+#if ZEN_USE_CACHE_TRACKER
+
+#	include <zencore/compactbinarybuilder.h>
+#	include <zencore/compactbinaryvalue.h>
+#	include <zencore/endian.h>
+#	include <zencore/filesystem.h>
+#	include <zencore/logging.h>
+#	include <zencore/scopeguard.h>
+#	include <zencore/string.h>
+
+#	include <zencore/testing.h>
+#	include <zencore/testutils.h>
+
+ZEN_THIRD_PARTY_INCLUDES_START
+#	pragma comment(lib, "Rpcrt4.lib")	// RocksDB made me do this
+#	include <fmt/format.h>
+#	include <rocksdb/db.h>
+#	include <tsl/robin_map.h>
+#	include <tsl/robin_set.h>
+#	include <gsl/gsl-lite.hpp>
+ZEN_THIRD_PARTY_INCLUDES_END
+
+namespace zen {
+
+namespace rocksdb = ROCKSDB_NAMESPACE;
+
+static constinit auto Epoch = std::chrono::time_point<std::chrono::system_clock>{};
+
+static uint64_t
+GetCurrentCacheTimeStamp()
+{
+	auto	 Duration = std::chrono::system_clock::now() - Epoch;
+	uint64_t Millis	  = std::chrono::duration_cast<std::chrono::milliseconds>(Duration).count();
+
+	return Millis;
+}
+
+struct CacheAccessSnapshot
+{
+public:
+	void TrackAccess(std::string_view BucketSegment, const IoHash& HashKey)
+	{
+		BucketTracker* Tracker = GetBucket(std::string(BucketSegment));
+
+		Tracker->Track(HashKey);
+	}
+
+	bool SerializeSnapshot(CbObjectWriter& Cbo)
+	{
+		bool					   Serialized = false;
+		RwLock::ExclusiveLockScope _(m_Lock);
+
+		for (const auto& Kv : m_BucketMapping)
+		{
+			if (m_Buckets[Kv.second]->Size())
+			{
+				Cbo.BeginArray(Kv.first);
+				m_Buckets[Kv.second]->SerializeSnapshotAndClear(Cbo);
+				Cbo.EndArray();
+				Serialized = true;
+			}
+		}
+
+		return Serialized;
+	}
+
+private:
+	struct BucketTracker
+	{
+		mutable RwLock		   Lock;
+		tsl::robin_set<IoHash> AccessedKeys;
+
+		void Track(const IoHash& HashKey)
+		{
+			if (RwLock::SharedLockScope _(Lock); AccessedKeys.contains(HashKey))
+			{
+				return;
+			}
+
+			RwLock::ExclusiveLockScope _(Lock);
+
+			AccessedKeys.insert(HashKey);
+		}
+
+		void SerializeSnapshotAndClear(CbObjectWriter& Cbo)
+		{
+			RwLock::ExclusiveLockScope _(Lock);
+
+			for (const IoHash& Hash : AccessedKeys)
+			{
+				Cbo.AddHash(Hash);
+			}
+
+			AccessedKeys.clear();
+		}
+
+		size_t Size() const
+		{
+			RwLock::SharedLockScope _(Lock);
+			return AccessedKeys.size();
+		}
+	};
+
+	BucketTracker* GetBucket(const std::string& BucketName)
+	{
+		RwLock::SharedLockScope _(m_Lock);
+
+		if (auto It = m_BucketMapping.find(BucketName); It == m_BucketMapping.end())
+		{
+			_.ReleaseNow();
+
+			return AddNewBucket(BucketName);
+		}
+		else
+		{
+			return m_Buckets[It->second].get();
+		}
+	}
+
+	BucketTracker* AddNewBucket(const std::string& BucketName)
+	{
+		RwLock::ExclusiveLockScope _(m_Lock);
+
+		if (auto It = m_BucketMapping.find(BucketName); It == m_BucketMapping.end())
+		{
+			const uint32_t BucketIndex = gsl::narrow<uint32_t>(m_Buckets.size());
+			m_Buckets.emplace_back(std::make_unique<BucketTracker>());
+			m_BucketMapping[BucketName] = BucketIndex;
+
+			return m_Buckets[BucketIndex].get();
+		}
+		else
+		{
+			return m_Buckets[It->second].get();
+		}
+	}
+
+	RwLock										m_Lock;
+	std::vector<std::unique_ptr<BucketTracker>> m_Buckets;
+	tsl::robin_map<std::string, uint32_t>		m_BucketMapping;
+};
+
+struct ZenCacheTracker::Impl
+{
+	Impl(std::filesystem::path StateDirectory)
+	{
+		std::filesystem::path StatsDbPath{StateDirectory / ".zdb"};
+
+		std::string RocksdbPath = StatsDbPath.string();
+
+		ZEN_DEBUG("opening tracker db at '{}'", RocksdbPath);
+
+		rocksdb::DB*	   Db = nullptr;
+		rocksdb::DBOptions Options;
+		Options.create_if_missing = true;
+
+		std::vector<std::string> ExistingColumnFamilies;
+		rocksdb::Status			 Status = rocksdb::DB::ListColumnFamilies(Options, RocksdbPath, &ExistingColumnFamilies);
+
+		std::vector<rocksdb::ColumnFamilyDescriptor> ColumnDescriptors;
+
+		if (Status.IsPathNotFound())
+		{
+			ColumnDescriptors.emplace_back(rocksdb::ColumnFamilyDescriptor{rocksdb::kDefaultColumnFamilyName, {}});
+		}
+		else if (Status.ok())
+		{
+			for (const std::string& Column : ExistingColumnFamilies)
+			{
+				rocksdb::ColumnFamilyDescriptor ColumnFamily;
+				ColumnFamily.name = Column;
+				ColumnDescriptors.push_back(ColumnFamily);
+			}
+		}
+		else
+		{
+			throw std::runtime_error(fmt::format("column family iteration failed for '{}': '{}'", RocksdbPath, Status.getState()).c_str());
+		}
+
+		Status = rocksdb::DB::Open(Options, RocksdbPath, ColumnDescriptors, &m_RocksDbColumnHandles, &Db);
+
+		if (!Status.ok())
+		{
+			throw std::runtime_error(fmt::format("database open failed for '{}': '{}'", RocksdbPath, Status.getState()).c_str());
+		}
+
+		m_RocksDb.reset(Db);
+	}
+
+	~Impl()
+	{
+		for (auto* Column : m_RocksDbColumnHandles)
+		{
+			delete Column;
+		}
+
+		m_RocksDbColumnHandles.clear();
+	}
+
+	struct KeyStruct
+	{
+		uint64_t TimestampLittleEndian;
+	};
+
+	void TrackAccess(std::string_view BucketSegment, const IoHash& HashKey) { m_CurrentSnapshot.TrackAccess(BucketSegment, HashKey); }
+
+	void SaveSnapshot()
+	{
+		CbObjectWriter Cbo;
+
+		if (m_CurrentSnapshot.SerializeSnapshot(Cbo))
+		{
+			IoBuffer SnapshotBuffer = Cbo.Save().GetBuffer().AsIoBuffer();
+
+			const KeyStruct Key{.TimestampLittleEndian = ToNetworkOrder(GetCurrentCacheTimeStamp())};
+			rocksdb::Slice	KeySlice{(const char*)&Key, sizeof Key};
+			rocksdb::Slice	ValueSlice{(char*)SnapshotBuffer.Data(), SnapshotBuffer.Size()};
+
+			rocksdb::WriteOptions Wo;
+			m_RocksDb->Put(Wo, KeySlice, ValueSlice);
+		}
+	}
+
+	void IterateSnapshots(std::function<void(uint64_t TimeStamp, CbObject Snapshot)>&& Callback)
+	{
+		rocksdb::ManagedSnapshot Snap(m_RocksDb.get());
+
+		rocksdb::ReadOptions Ro;
+		Ro.snapshot = Snap.snapshot();
+
+		std::unique_ptr<rocksdb::Iterator> It{m_RocksDb->NewIterator(Ro)};
+
+		const KeyStruct ZeroKey{.TimestampLittleEndian = 0};
+		rocksdb::Slice	ZeroKeySlice{(const char*)&ZeroKey, sizeof ZeroKey};
+
+		It->Seek(ZeroKeySlice);
+
+		while (It->Valid())
+		{
+			rocksdb::Slice KeySlice	  = It->key();
+			rocksdb::Slice ValueSlice = It->value();
+
+			if (KeySlice.size() == sizeof(KeyStruct))
+			{
+				IoBuffer ValueBuffer(IoBuffer::Wrap, ValueSlice.data(), ValueSlice.size());
+
+				CbObject Value = LoadCompactBinaryObject(ValueBuffer);
+
+				uint64_t Key = FromNetworkOrder(*reinterpret_cast<const uint64_t*>(KeySlice.data()));
+
+				Callback(Key, Value);
+			}
+
+			It->Next();
+		}
+	}
+
+	std::unique_ptr<rocksdb::DB>			  m_RocksDb;
+	std::vector<rocksdb::ColumnFamilyHandle*> m_RocksDbColumnHandles;
+	CacheAccessSnapshot						  m_CurrentSnapshot;
+};
+
+ZenCacheTracker::ZenCacheTracker(std::filesystem::path StateDirectory) : m_Impl(new Impl(StateDirectory))
+{
+}
+
+ZenCacheTracker::~ZenCacheTracker()
+{
+	delete m_Impl;
+}
+
+void
+ZenCacheTracker::TrackAccess(std::string_view BucketSegment, const IoHash& HashKey)
+{
+	m_Impl->TrackAccess(BucketSegment, HashKey);
+}
+
+void
+ZenCacheTracker::SaveSnapshot()
+{
+	m_Impl->SaveSnapshot();
+}
+
+void
+ZenCacheTracker::IterateSnapshots(std::function<void(uint64_t TimeStamp, CbObject Snapshot)>&& Callback)
+{
+	m_Impl->IterateSnapshots(std::move(Callback));
+}
+
+#	if ZEN_WITH_TESTS
+
+TEST_CASE("z$.tracker")
+{
+	using namespace std::literals;
+
+	const uint64_t t0 = GetCurrentCacheTimeStamp();
+
+	ScopedTemporaryDirectory TempDir;
+
+	ZenCacheTracker Zcs(TempDir.Path());
+
+	tsl::robin_set<IoHash> KeyHashes;
+
+	for (int i = 0; i < 10000; ++i)
+	{
+		IoHash KeyHash = IoHash::HashBuffer(&i, sizeof i);
+
+		KeyHashes.insert(KeyHash);
+
+		Zcs.TrackAccess("foo"sv, KeyHash);
+	}
+
+	for (int i = 0; i < 10000; ++i)
+	{
+		IoHash KeyHash = IoHash::HashBuffer(&i, sizeof i);
+
+		Zcs.TrackAccess("foo"sv, KeyHash);
+	}
+
+	Zcs.SaveSnapshot();
+
+	for (int n = 0; n < 10; ++n)
+	{
+		for (int i = 0; i < 1000; ++i)
+		{
+			const int Index	  = i + n * 1000;
+			IoHash	  KeyHash = IoHash::HashBuffer(&Index, sizeof Index);
+
+			Zcs.TrackAccess("foo"sv, KeyHash);
+		}
+
+		Zcs.SaveSnapshot();
+	}
+
+	Zcs.SaveSnapshot();
+
+	const uint64_t t1 = GetCurrentCacheTimeStamp();
+
+	int SnapshotCount = 0;
+
+	Zcs.IterateSnapshots([&](uint64_t TimeStamp, CbObject Snapshot) {
+		CHECK(TimeStamp >= t0);
+		CHECK(TimeStamp <= t1);
+
+		for (auto& Field : Snapshot)
+		{
+			CHECK_EQ(Field.GetName(), "foo"sv);
+
+			const CbArray& Array = Field.AsArray();
+
+			for (const auto& Element : Array)
+			{
+				CHECK(KeyHashes.contains(Element.GetValue().AsHash()));
+			}
+		}
+
+		++SnapshotCount;
+	});
+
+	CHECK_EQ(SnapshotCount, 11);
+}
+
+#	endif
+
+void
+cachetracker_forcelink()
+{
+}
+
+}  // namespace zen
+
+#endif	// ZEN_USE_CACHE_TRACKER
diff --git a/src/zenserver/cache/cachetracking.h b/src/zenserver/cache/cachetracking.h
new file mode 100644
index 000000000..fdfe1a4c7
--- /dev/null
+++ b/src/zenserver/cache/cachetracking.h
@@ -0,0 +1,41 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include <zencore/iohash.h>
+
+#include <stdint.h>
+#include <filesystem>
+#include <functional>
+
+namespace zen {
+
+#define ZEN_USE_CACHE_TRACKER 0
+#if ZEN_USE_CACHE_TRACKER
+
+class CbObject;
+
+/**
+ */
+
+class ZenCacheTracker
+{
+public:
+	ZenCacheTracker(std::filesystem::path StateDirectory);
+	~ZenCacheTracker();
+
+	void TrackAccess(std::string_view BucketSegment, const IoHash& HashKey);
+	void SaveSnapshot();
+	void IterateSnapshots(std::function<void(uint64_t TimeStamp, CbObject Snapshot)>&& Callback);
+
+private:
+	struct Impl;
+
+	Impl* m_Impl = nullptr;
+};
+
+void cachetracker_forcelink();
+
+#endif	// ZEN_USE_CACHE_TRACKER
+
+}  // namespace zen
diff --git a/src/zenserver/cache/structuredcache.cpp b/src/zenserver/cache/structuredcache.cpp
new file mode 100644
index 000000000..90e905bf6
--- /dev/null
+++ b/src/zenserver/cache/structuredcache.cpp
@@ -0,0 +1,3159 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include "structuredcache.h"
+
+#include <zencore/compactbinary.h>
+#include <zencore/compactbinarybuilder.h>
+#include <zencore/compactbinarypackage.h>
+#include <zencore/compactbinaryvalidation.h>
+#include <zencore/compress.h>
+#include <zencore/enumflags.h>
+#include <zencore/fmtutils.h>
+#include <zencore/logging.h>
+#include <zencore/scopeguard.h>
+#include <zencore/stream.h>
+#include <zencore/timer.h>
+#include <zencore/trace.h>
+#include <zencore/workthreadpool.h>
+#include <zenhttp/httpserver.h>
+#include <zenhttp/httpshared.h>
+#include <zenutil/cache/cache.h>
+#include <zenutil/cache/rpcrecording.h>
+
+#include "monitoring/httpstats.h"
+#include "structuredcachestore.h"
+#include "upstream/jupiter.h"
+#include "upstream/upstreamcache.h"
+#include "upstream/zen.h"
+#include "zenstore/cidstore.h"
+#include "zenstore/scrubcontext.h"
+
+#include <algorithm>
+#include <atomic>
+#include <filesystem>
+#include <queue>
+#include <thread>
+
+#include <cpr/cpr.h>
+#include <gsl/gsl-lite.hpp>
+
+#if ZEN_WITH_TESTS
+#	include <zencore/testing.h>
+#	include <zencore/testutils.h>
+#endif
+
+namespace zen {
+
+using namespace std::literals;
+
+//////////////////////////////////////////////////////////////////////////
+
+CachePolicy
+ParseCachePolicy(const HttpServerRequest::QueryParams& QueryParams)
+{
+	std::string_view PolicyText = QueryParams.GetValue("Policy"sv);
+	return !PolicyText.empty() ? zen::ParseCachePolicy(PolicyText) : CachePolicy::Default;
+}
+
+CacheRecordPolicy
+LoadCacheRecordPolicy(CbObjectView Object, CachePolicy DefaultPolicy = CachePolicy::Default)
+{
+	OptionalCacheRecordPolicy Policy = CacheRecordPolicy::Load(Object);
+	return Policy ? std::move(Policy).Get() : CacheRecordPolicy(DefaultPolicy);
+}
+
+struct AttachmentCount
+{
+	uint32_t New	 = 0;
+	uint32_t Valid	 = 0;
+	uint32_t Invalid = 0;
+	uint32_t Total	 = 0;
+};
+
+struct PutRequestData
+{
+	std::string		  Namespace;
+	CacheKey		  Key;
+	CbObjectView	  RecordObject;
+	CacheRecordPolicy Policy;
+};
+
+namespace {
+	static constinit std::string_view HttpZCacheRPCPrefix			= "$rpc"sv;
+	static constinit std::string_view HttpZCacheUtilStartRecording	= "exec$/start-recording"sv;
+	static constinit std::string_view HttpZCacheUtilStopRecording	= "exec$/stop-recording"sv;
+	static constinit std::string_view HttpZCacheUtilReplayRecording = "exec$/replay-recording"sv;
+	static constinit std::string_view HttpZCacheDetailsPrefix		= "details$"sv;
+
+	struct HttpRequestData
+	{
+		std::optional<std::string> Namespace;
+		std::optional<std::string> Bucket;
+		std::optional<IoHash>	   HashKey;
+		std::optional<IoHash>	   ValueContentId;
+	};
+
+	constinit AsciiSet ValidNamespaceNameCharactersSet{"abcdefghijklmnopqrstuvwxyz0123456789-_.ABCDEFGHIJKLMNOPQRSTUVWXYZ"};
+	constinit AsciiSet ValidBucketNameCharactersSet{"abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"};
+
+	std::optional<std::string> GetValidNamespaceName(std::string_view Name)
+	{
+		if (Name.empty())
+		{
+			ZEN_WARN("Namespace is invalid, empty namespace is not allowed");
+			return {};
+		}
+
+		if (Name.length() > 64)
+		{
+			ZEN_WARN("Namespace '{}' is invalid, length exceeds 64 characters", Name);
+			return {};
+		}
+
+		if (!AsciiSet::HasOnly(Name, ValidNamespaceNameCharactersSet))
+		{
+			ZEN_WARN("Namespace '{}' is invalid, invalid characters detected", Name);
+			return {};
+		}
+
+		return ToLower(Name);
+	}
+
+	std::optional<std::string> GetValidBucketName(std::string_view Name)
+	{
+		if (Name.empty())
+		{
+			ZEN_WARN("Bucket name is invalid, empty bucket name is not allowed");
+			return {};
+		}
+
+		if (!AsciiSet::HasOnly(Name, ValidBucketNameCharactersSet))
+		{
+			ZEN_WARN("Bucket name '{}' is invalid, invalid characters detected", Name);
+			return {};
+		}
+
+		return ToLower(Name);
+	}
+
+	std::optional<IoHash> GetValidIoHash(std::string_view Hash)
+	{
+		if (Hash.length() != IoHash::StringLength)
+		{
+			return {};
+		}
+
+		IoHash KeyHash;
+		if (!ParseHexBytes(Hash.data(), Hash.size(), KeyHash.Hash))
+		{
+			return {};
+		}
+		return KeyHash;
+	}
+
+	bool HttpRequestParseRelativeUri(std::string_view Key, HttpRequestData& Data)
+	{
+		std::vector<std::string_view> Tokens;
+		uint32_t					  TokenCount = ForEachStrTok(Key, '/', [&](const std::string_view& Token) {
+			 Tokens.push_back(Token);
+			 return true;
+		 });
+
+		switch (TokenCount)
+		{
+			case 0:
+				return true;
+			case 1:
+				Data.Namespace = GetValidNamespaceName(Tokens[0]);
+				return Data.Namespace.has_value();
+			case 2:
+				{
+					std::optional<IoHash> PossibleHashKey = GetValidIoHash(Tokens[1]);
+					if (PossibleHashKey.has_value())
+					{
+						// Legacy bucket/key request
+						Data.Bucket = GetValidBucketName(Tokens[0]);
+						if (!Data.Bucket.has_value())
+						{
+							return false;
+						}
+						Data.HashKey   = PossibleHashKey;
+						Data.Namespace = ZenCacheStore::DefaultNamespace;
+						return true;
+					}
+					Data.Namespace = GetValidNamespaceName(Tokens[0]);
+					if (!Data.Namespace.has_value())
+					{
+						return false;
+					}
+					Data.Bucket = GetValidBucketName(Tokens[1]);
+					if (!Data.Bucket.has_value())
+					{
+						return false;
+					}
+					return true;
+				}
+			case 3:
+				{
+					std::optional<IoHash> PossibleHashKey = GetValidIoHash(Tokens[1]);
+					if (PossibleHashKey.has_value())
+					{
+						// Legacy bucket/key/valueid request
+						Data.Bucket = GetValidBucketName(Tokens[0]);
+						if (!Data.Bucket.has_value())
+						{
+							return false;
+						}
+						Data.HashKey		= PossibleHashKey;
+						Data.ValueContentId = GetValidIoHash(Tokens[2]);
+						if (!Data.ValueContentId.has_value())
+						{
+							return false;
+						}
+						Data.Namespace = ZenCacheStore::DefaultNamespace;
+						return true;
+					}
+					Data.Namespace = GetValidNamespaceName(Tokens[0]);
+					if (!Data.Namespace.has_value())
+					{
+						return false;
+					}
+					Data.Bucket = GetValidBucketName(Tokens[1]);
+					if (!Data.Bucket.has_value())
+					{
+						return false;
+					}
+					Data.HashKey = GetValidIoHash(Tokens[2]);
+					if (!Data.HashKey)
+					{
+						return false;
+					}
+					return true;
+				}
+			case 4:
+				{
+					Data.Namespace = GetValidNamespaceName(Tokens[0]);
+					if (!Data.Namespace.has_value())
+					{
+						return false;
+					}
+
+					Data.Bucket = GetValidBucketName(Tokens[1]);
+					if (!Data.Bucket.has_value())
+					{
+						return false;
+					}
+
+					Data.HashKey = GetValidIoHash(Tokens[2]);
+					if (!Data.HashKey.has_value())
+					{
+						return false;
+					}
+
+					Data.ValueContentId = GetValidIoHash(Tokens[3]);
+					if (!Data.ValueContentId.has_value())
+					{
+						return false;
+					}
+					return true;
+				}
+			default:
+				return false;
+		}
+	}
+
+	std::optional<std::string> GetRpcRequestNamespace(const CbObjectView Params)
+	{
+		CbFieldView NamespaceField = Params["Namespace"sv];
+		if (!NamespaceField)
+		{
+			return std::string(ZenCacheStore::DefaultNamespace);
+		}
+
+		if (NamespaceField.HasError())
+		{
+			return {};
+		}
+		if (!NamespaceField.IsString())
+		{
+			return {};
+		}
+		return GetValidNamespaceName(NamespaceField.AsString());
+	}
+
+	bool GetRpcRequestCacheKey(const CbObjectView& KeyView, CacheKey& Key)
+	{
+		CbFieldView BucketField = KeyView["Bucket"sv];
+		if (BucketField.HasError())
+		{
+			return false;
+		}
+		if (!BucketField.IsString())
+		{
+			return false;
+		}
+		std::optional<std::string> Bucket = GetValidBucketName(BucketField.AsString());
+		if (!Bucket.has_value())
+		{
+			return false;
+		}
+		CbFieldView HashField = KeyView["Hash"sv];
+		if (HashField.HasError())
+		{
+			return false;
+		}
+		if (!HashField.IsHash())
+		{
+			return false;
+		}
+		IoHash Hash = HashField.AsHash();
+		Key			= CacheKey::Create(*Bucket, Hash);
+		return true;
+	}
+
+}  // namespace
+
+//////////////////////////////////////////////////////////////////////////
+
+HttpStructuredCacheService::HttpStructuredCacheService(ZenCacheStore&	  InCacheStore,
+													   CidStore&		  InCidStore,
+													   HttpStatsService&  StatsService,
+													   HttpStatusService& StatusService,
+													   UpstreamCache&	  UpstreamCache)
+: m_Log(logging::Get("cache"))
+, m_CacheStore(InCacheStore)
+, m_StatsService(StatsService)
+, m_StatusService(StatusService)
+, m_CidStore(InCidStore)
+, m_UpstreamCache(UpstreamCache)
+{
+	m_StatsService.RegisterHandler("z$", *this);
+	m_StatusService.RegisterHandler("z$", *this);
+}
+
+HttpStructuredCacheService::~HttpStructuredCacheService()
+{
+	ZEN_INFO("closing structured cache");
+	m_RequestRecorder.reset();
+
+	m_StatsService.UnregisterHandler("z$", *this);
+	m_StatusService.UnregisterHandler("z$", *this);
+}
+
+const char*
+HttpStructuredCacheService::BaseUri() const
+{
+	return "/z$/";
+}
+
+void
+HttpStructuredCacheService::Flush()
+{
+	m_CacheStore.Flush();
+}
+
+void
+HttpStructuredCacheService::Scrub(ScrubContext& Ctx)
+{
+	if (m_LastScrubTime == Ctx.ScrubTimestamp())
+	{
+		return;
+	}
+
+	m_LastScrubTime = Ctx.ScrubTimestamp();
+
+	m_CidStore.Scrub(Ctx);
+	m_CacheStore.Scrub(Ctx);
+}
+
+void
+HttpStructuredCacheService::HandleDetailsRequest(HttpServerRequest& Request)
+{
+	std::string_view		 Key = Request.RelativeUri();
+	std::vector<std::string> Tokens;
+	uint32_t				 TokenCount = ForEachStrTok(Key, '/', [&Tokens](std::string_view Token) {
+		Tokens.push_back(std::string(Token));
+		return true;
+	});
+	std::string				 FilterNamespace;
+	std::string				 FilterBucket;
+	std::string				 FilterValue;
+	switch (TokenCount)
+	{
+		case 1:
+			break;
+		case 2:
+			{
+				FilterNamespace = Tokens[1];
+				if (FilterNamespace.empty())
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+				}
+			}
+			break;
+		case 3:
+			{
+				FilterNamespace = Tokens[1];
+				if (FilterNamespace.empty())
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+				}
+				FilterBucket = Tokens[2];
+				if (FilterBucket.empty())
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+				}
+			}
+			break;
+		case 4:
+			{
+				FilterNamespace = Tokens[1];
+				if (FilterNamespace.empty())
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+				}
+				FilterBucket = Tokens[2];
+				if (FilterBucket.empty())
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+				}
+				FilterValue = Tokens[3];
+				if (FilterValue.empty())
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+				}
+			}
+			break;
+		default:
+			return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+	}
+
+	HttpServerRequest::QueryParams Params			 = Request.GetQueryParams();
+	bool						   CSV				 = Params.GetValue("csv") == "true";
+	bool						   Details			 = Params.GetValue("details") == "true";
+	bool						   AttachmentDetails = Params.GetValue("attachmentdetails") == "true";
+
+	std::chrono::seconds NowSeconds	  = std::chrono::duration_cast<std::chrono::seconds>(GcClock::Now().time_since_epoch());
+	CacheValueDetails	 ValueDetails = m_CacheStore.GetValueDetails(FilterNamespace, FilterBucket, FilterValue);
+
+	if (CSV)
+	{
+		ExtendableStringBuilder<4096> CSVWriter;
+		if (AttachmentDetails)
+		{
+			CSVWriter << "Namespace, Bucket, Key, Cid, Size";
+		}
+		else if (Details)
+		{
+			CSVWriter << "Namespace, Bucket, Key, Size, RawSize, RawHash, ContentType, Age, AttachmentsCount, AttachmentsSize";
+		}
+		else
+		{
+			CSVWriter << "Namespace, Bucket, Key";
+		}
+		for (const auto& NamespaceIt : ValueDetails.Namespaces)
+		{
+			const std::string& Namespace = NamespaceIt.first;
+			for (const auto& BucketIt : NamespaceIt.second.Buckets)
+			{
+				const std::string& Bucket = BucketIt.first;
+				for (const auto& ValueIt : BucketIt.second.Values)
+				{
+					if (AttachmentDetails)
+					{
+						for (const IoHash& Hash : ValueIt.second.Attachments)
+						{
+							IoBuffer Payload = m_CidStore.FindChunkByCid(Hash);
+							CSVWriter << "\r\n"
+									  << Namespace << "," << Bucket << "," << ValueIt.first.ToHexString() << ", " << Hash.ToHexString()
+									  << ", " << gsl::narrow<uint64_t>(Payload.GetSize());
+						}
+					}
+					else if (Details)
+					{
+						std::chrono::seconds LastAccessedSeconds = std::chrono::duration_cast<std::chrono::seconds>(
+							GcClock::TimePointFromTick(ValueIt.second.LastAccess).time_since_epoch());
+						CSVWriter << "\r\n"
+								  << Namespace << "," << Bucket << "," << ValueIt.first.ToHexString() << ", " << ValueIt.second.Size << ","
+								  << ValueIt.second.RawSize << "," << ValueIt.second.RawHash.ToHexString() << ", "
+								  << ToString(ValueIt.second.ContentType) << ", " << (NowSeconds.count() - LastAccessedSeconds.count())
+								  << ", " << gsl::narrow<uint64_t>(ValueIt.second.Attachments.size());
+						size_t AttachmentsSize = 0;
+						for (const IoHash& Hash : ValueIt.second.Attachments)
+						{
+							IoBuffer Payload = m_CidStore.FindChunkByCid(Hash);
+							AttachmentsSize += Payload.GetSize();
+						}
+						CSVWriter << ", " << gsl::narrow<uint64_t>(AttachmentsSize);
+					}
+					else
+					{
+						CSVWriter << "\r\n" << Namespace << "," << Bucket << "," << ValueIt.first.ToHexString();
+					}
+				}
+			}
+		}
+		return Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kText, CSVWriter.ToView());
+	}
+	else
+	{
+		CbObjectWriter Cbo;
+		Cbo.BeginArray("namespaces");
+		{
+			for (const auto& NamespaceIt : ValueDetails.Namespaces)
+			{
+				const std::string& Namespace = NamespaceIt.first;
+				Cbo.BeginObject();
+				{
+					Cbo.AddString("name", Namespace);
+					Cbo.BeginArray("buckets");
+					{
+						for (const auto& BucketIt : NamespaceIt.second.Buckets)
+						{
+							const std::string& Bucket = BucketIt.first;
+							Cbo.BeginObject();
+							{
+								Cbo.AddString("name", Bucket);
+								Cbo.BeginArray("values");
+								{
+									for (const auto& ValueIt : BucketIt.second.Values)
+									{
+										std::chrono::seconds LastAccessedSeconds = std::chrono::duration_cast<std::chrono::seconds>(
+											GcClock::TimePointFromTick(ValueIt.second.LastAccess).time_since_epoch());
+										Cbo.BeginObject();
+										{
+											Cbo.AddHash("key", ValueIt.first);
+											if (Details)
+											{
+												Cbo.AddInteger("size", ValueIt.second.Size);
+												if (ValueIt.second.Size > 0 && ValueIt.second.RawSize != 0 &&
+													ValueIt.second.RawSize != ValueIt.second.Size)
+												{
+													Cbo.AddInteger("rawsize", ValueIt.second.RawSize);
+													Cbo.AddHash("rawhash", ValueIt.second.RawHash);
+												}
+												Cbo.AddString("contenttype", ToString(ValueIt.second.ContentType));
+												Cbo.AddInteger("age", NowSeconds.count() - LastAccessedSeconds.count());
+												if (ValueIt.second.Attachments.size() > 0)
+												{
+													if (AttachmentDetails)
+													{
+														Cbo.BeginArray("attachments");
+														{
+															for (const IoHash& Hash : ValueIt.second.Attachments)
+															{
+																Cbo.BeginObject();
+																Cbo.AddHash("cid", Hash);
+																IoBuffer Payload = m_CidStore.FindChunkByCid(Hash);
+																Cbo.AddInteger("size", gsl::narrow<uint64_t>(Payload.GetSize()));
+																Cbo.EndObject();
+															}
+														}
+														Cbo.EndArray();
+													}
+													else
+													{
+														Cbo.AddInteger("attachmentcount",
+																	   gsl::narrow<uint64_t>(ValueIt.second.Attachments.size()));
+														size_t AttachmentsSize = 0;
+														for (const IoHash& Hash : ValueIt.second.Attachments)
+														{
+															IoBuffer Payload = m_CidStore.FindChunkByCid(Hash);
+															AttachmentsSize += Payload.GetSize();
+														}
+														Cbo.AddInteger("attachmentssize", gsl::narrow<uint64_t>(AttachmentsSize));
+													}
+												}
+											}
+										}
+										Cbo.EndObject();
+									}
+								}
+								Cbo.EndArray();
+							}
+							Cbo.EndObject();
+						}
+					}
+					Cbo.EndArray();
+				}
+				Cbo.EndObject();
+			}
+		}
+		Cbo.EndArray();
+		Request.WriteResponse(HttpResponseCode::OK, Cbo.Save());
+	}
+}
+
+void
+HttpStructuredCacheService::HandleRequest(HttpServerRequest& Request)
+{
+	metrics::OperationTiming::Scope $(m_HttpRequests);
+
+	std::string_view Key = Request.RelativeUri();
+	if (Key == HttpZCacheRPCPrefix)
+	{
+		return HandleRpcRequest(Request);
+	}
+
+	if (Key == HttpZCacheUtilStartRecording)
+	{
+		m_RequestRecorder.reset();
+		HttpServerRequest::QueryParams Params	  = Request.GetQueryParams();
+		std::string					   RecordPath = cpr::util::urlDecode(std::string(Params.GetValue("path")));
+		m_RequestRecorder						  = cache::MakeDiskRequestRecorder(RecordPath);
+		Request.WriteResponse(HttpResponseCode::OK);
+		return;
+	}
+	if (Key == HttpZCacheUtilStopRecording)
+	{
+		m_RequestRecorder.reset();
+		Request.WriteResponse(HttpResponseCode::OK);
+		return;
+	}
+	if (Key == HttpZCacheUtilReplayRecording)
+	{
+		m_RequestRecorder.reset();
+		HttpServerRequest::QueryParams Params	   = Request.GetQueryParams();
+		std::string					   RecordPath  = cpr::util::urlDecode(std::string(Params.GetValue("path")));
+		uint32_t					   ThreadCount = std::thread::hardware_concurrency();
+		if (auto Param = Params.GetValue("thread_count"); Param.empty() == false)
+		{
+			if (auto Value = ParseInt<uint64_t>(Param))
+			{
+				ThreadCount = gsl::narrow<uint32_t>(Value.value());
+			}
+		}
+		std::unique_ptr<cache::IRpcRequestReplayer> Replayer(cache::MakeDiskRequestReplayer(RecordPath, false));
+		ReplayRequestRecorder(*Replayer, ThreadCount < 1 ? 1 : ThreadCount);
+		Request.WriteResponse(HttpResponseCode::OK);
+		return;
+	}
+	if (Key.starts_with(HttpZCacheDetailsPrefix))
+	{
+		HandleDetailsRequest(Request);
+		return;
+	}
+
+	HttpRequestData RequestData;
+	if (!HttpRequestParseRelativeUri(Key, RequestData))
+	{
+		return Request.WriteResponse(HttpResponseCode::BadRequest);	 // invalid URL
+	}
+
+	if (RequestData.ValueContentId.has_value())
+	{
+		ZEN_ASSERT(RequestData.Namespace.has_value());
+		ZEN_ASSERT(RequestData.Bucket.has_value());
+		ZEN_ASSERT(RequestData.HashKey.has_value());
+		CacheRef Ref = {.Namespace		= RequestData.Namespace.value(),
+						.BucketSegment	= RequestData.Bucket.value(),
+						.HashKey		= RequestData.HashKey.value(),
+						.ValueContentId = RequestData.ValueContentId.value()};
+		return HandleCacheChunkRequest(Request, Ref, ParseCachePolicy(Request.GetQueryParams()));
+	}
+
+	if (RequestData.HashKey.has_value())
+	{
+		ZEN_ASSERT(RequestData.Namespace.has_value());
+		ZEN_ASSERT(RequestData.Bucket.has_value());
+		CacheRef Ref = {.Namespace		= RequestData.Namespace.value(),
+						.BucketSegment	= RequestData.Bucket.value(),
+						.HashKey		= RequestData.HashKey.value(),
+						.ValueContentId = IoHash::Zero};
+		return HandleCacheRecordRequest(Request, Ref, ParseCachePolicy(Request.GetQueryParams()));
+	}
+
+	if (RequestData.Bucket.has_value())
+	{
+		ZEN_ASSERT(RequestData.Namespace.has_value());
+		return HandleCacheBucketRequest(Request, RequestData.Namespace.value(), RequestData.Bucket.value());
+	}
+
+	if (RequestData.Namespace.has_value())
+	{
+		return HandleCacheNamespaceRequest(Request, RequestData.Namespace.value());
+	}
+	return HandleCacheRequest(Request);
+}
+
+void
+HttpStructuredCacheService::HandleCacheRequest(HttpServerRequest& Request)
+{
+	switch (Request.RequestVerb())
+	{
+		case HttpVerb::kHead:
+		case HttpVerb::kGet:
+			{
+				ZenCacheStore::Info Info = m_CacheStore.GetInfo();
+
+				CbObjectWriter ResponseWriter;
+
+				ResponseWriter.BeginObject("Configuration");
+				{
+					ExtendableStringBuilder<128> BasePathString;
+					BasePathString << Info.Config.BasePath.u8string();
+					ResponseWriter.AddString("BasePath"sv, BasePathString.ToView());
+					ResponseWriter.AddBool("AllowAutomaticCreationOfNamespaces", Info.Config.AllowAutomaticCreationOfNamespaces);
+				}
+				ResponseWriter.EndObject();
+
+				std::sort(begin(Info.NamespaceNames), end(Info.NamespaceNames), [](std::string_view L, std::string_view R) {
+					return L.compare(R) < 0;
+				});
+				ResponseWriter.BeginArray("Namespaces");
+				for (const std::string& NamespaceName : Info.NamespaceNames)
+				{
+					ResponseWriter.AddString(NamespaceName);
+				}
+				ResponseWriter.EndArray();
+				ResponseWriter.BeginObject("StorageSize");
+				{
+					ResponseWriter.AddInteger("DiskSize", Info.StorageSize.DiskSize);
+					ResponseWriter.AddInteger("MemorySize", Info.StorageSize.MemorySize);
+				}
+
+				ResponseWriter.EndObject();
+
+				ResponseWriter.AddInteger("DiskEntryCount", Info.DiskEntryCount);
+				ResponseWriter.AddInteger("MemoryEntryCount", Info.MemoryEntryCount);
+
+				return Request.WriteResponse(HttpResponseCode::OK, ResponseWriter.Save());
+			}
+			break;
+	}
+}
+
+void
+HttpStructuredCacheService::HandleCacheNamespaceRequest(HttpServerRequest& Request, std::string_view NamespaceName)
+{
+	switch (Request.RequestVerb())
+	{
+		case HttpVerb::kHead:
+		case HttpVerb::kGet:
+			{
+				std::optional<ZenCacheNamespace::Info> Info = m_CacheStore.GetNamespaceInfo(NamespaceName);
+				if (!Info.has_value())
+				{
+					return Request.WriteResponse(HttpResponseCode::NotFound);
+				}
+
+				CbObjectWriter ResponseWriter;
+
+				ResponseWriter.BeginObject("Configuration");
+				{
+					ExtendableStringBuilder<128> BasePathString;
+					BasePathString << Info->Config.RootDir.u8string();
+					ResponseWriter.AddString("RootDir"sv, BasePathString.ToView());
+					ResponseWriter.AddInteger("DiskLayerThreshold"sv, Info->Config.DiskLayerThreshold);
+				}
+				ResponseWriter.EndObject();
+
+				std::sort(begin(Info->BucketNames), end(Info->BucketNames), [](std::string_view L, std::string_view R) {
+					return L.compare(R) < 0;
+				});
+
+				ResponseWriter.BeginArray("Buckets"sv);
+				for (const std::string& BucketName : Info->BucketNames)
+				{
+					ResponseWriter.AddString(BucketName);
+				}
+				ResponseWriter.EndArray();
+
+				ResponseWriter.BeginObject("StorageSize"sv);
+				{
+					ResponseWriter.AddInteger("DiskSize"sv, Info->DiskLayerInfo.TotalSize);
+					ResponseWriter.AddInteger("MemorySize"sv, Info->MemoryLayerInfo.TotalSize);
+				}
+				ResponseWriter.EndObject();
+
+				ResponseWriter.AddInteger("DiskEntryCount", Info->DiskLayerInfo.EntryCount);
+				ResponseWriter.AddInteger("MemoryEntryCount", Info->MemoryLayerInfo.EntryCount);
+
+				return Request.WriteResponse(HttpResponseCode::OK, ResponseWriter.Save());
+			}
+			break;
+
+		case HttpVerb::kDelete:
+			// Drop namespace
+			{
+				if (m_CacheStore.DropNamespace(NamespaceName))
+				{
+					return Request.WriteResponse(HttpResponseCode::OK);
+				}
+				else
+				{
+					return Request.WriteResponse(HttpResponseCode::NotFound);
+				}
+			}
+			break;
+
+		default:
+			break;
+	}
+}
+
+void
+HttpStructuredCacheService::HandleCacheBucketRequest(HttpServerRequest& Request,
+													 std::string_view	NamespaceName,
+													 std::string_view	BucketName)
+{
+	switch (Request.RequestVerb())
+	{
+		case HttpVerb::kHead:
+		case HttpVerb::kGet:
+			{
+				std::optional<ZenCacheNamespace::BucketInfo> Info = m_CacheStore.GetBucketInfo(NamespaceName, BucketName);
+				if (!Info.has_value())
+				{
+					return Request.WriteResponse(HttpResponseCode::NotFound);
+				}
+
+				CbObjectWriter ResponseWriter;
+
+				ResponseWriter.BeginObject("StorageSize");
+				{
+					ResponseWriter.AddInteger("DiskSize", Info->DiskLayerInfo.TotalSize);
+					ResponseWriter.AddInteger("MemorySize", Info->MemoryLayerInfo.TotalSize);
+				}
+				ResponseWriter.EndObject();
+
+				ResponseWriter.AddInteger("DiskEntryCount", Info->DiskLayerInfo.EntryCount);
+				ResponseWriter.AddInteger("MemoryEntryCount", Info->MemoryLayerInfo.EntryCount);
+
+				return Request.WriteResponse(HttpResponseCode::OK, ResponseWriter.Save());
+			}
+			break;
+
+		case HttpVerb::kDelete:
+			// Drop bucket
+			{
+				if (m_CacheStore.DropBucket(NamespaceName, BucketName))
+				{
+					return Request.WriteResponse(HttpResponseCode::OK);
+				}
+				else
+				{
+					return Request.WriteResponse(HttpResponseCode::NotFound);
+				}
+			}
+			break;
+
+		default:
+			break;
+	}
+}
+
+void
+HttpStructuredCacheService::HandleCacheRecordRequest(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl)
+{
+	switch (Request.RequestVerb())
+	{
+		case HttpVerb::kHead:
+		case HttpVerb::kGet:
+			{
+				HandleGetCacheRecord(Request, Ref, PolicyFromUrl);
+			}
+			break;
+
+		case HttpVerb::kPut:
+			HandlePutCacheRecord(Request, Ref, PolicyFromUrl);
+			break;
+		default:
+			break;
+	}
+}
+
+void
+HttpStructuredCacheService::HandleGetCacheRecord(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl)
+{
+	const ZenContentType AcceptType	   = Request.AcceptContentType();
+	const bool			 SkipData	   = EnumHasAllFlags(PolicyFromUrl, CachePolicy::SkipData);
+	const bool			 PartialRecord = EnumHasAllFlags(PolicyFromUrl, CachePolicy::PartialRecord);
+
+	bool		  Success = false;
+	ZenCacheValue ClientResultValue;
+	if (!EnumHasAnyFlags(PolicyFromUrl, CachePolicy::Query))
+	{
+		return Request.WriteResponse(HttpResponseCode::OK);
+	}
+
+	Stopwatch Timer;
+
+	if (EnumHasAllFlags(PolicyFromUrl, CachePolicy::QueryLocal) &&
+		m_CacheStore.Get(Ref.Namespace, Ref.BucketSegment, Ref.HashKey, ClientResultValue))
+	{
+		Success					   = true;
+		ZenContentType ContentType = ClientResultValue.Value.GetContentType();
+
+		if (AcceptType == ZenContentType::kCbPackage)
+		{
+			if (ContentType == ZenContentType::kCbObject)
+			{
+				CbPackage Package;
+				uint32_t  MissingCount = 0;
+
+				CbObjectView CacheRecord(ClientResultValue.Value.Data());
+				CacheRecord.IterateAttachments([this, &MissingCount, &Package, SkipData](CbFieldView AttachmentHash) {
+					if (SkipData)
+					{
+						if (!m_CidStore.ContainsChunk(AttachmentHash.AsHash()))
+						{
+							MissingCount++;
+						}
+					}
+					else
+					{
+						if (IoBuffer Chunk = m_CidStore.FindChunkByCid(AttachmentHash.AsHash()))
+						{
+							CompressedBuffer Compressed = CompressedBuffer::FromCompressedNoValidate(std::move(Chunk));
+							Package.AddAttachment(CbAttachment(Compressed, AttachmentHash.AsHash()));
+						}
+						else
+						{
+							MissingCount++;
+						}
+					}
+				});
+
+				Success = MissingCount == 0 || PartialRecord;
+
+				if (Success)
+				{
+					Package.SetObject(LoadCompactBinaryObject(ClientResultValue.Value));
+
+					BinaryWriter MemStream;
+					Package.Save(MemStream);
+
+					ClientResultValue.Value = IoBuffer(IoBuffer::Clone, MemStream.Data(), MemStream.Size());
+					ClientResultValue.Value.SetContentType(HttpContentType::kCbPackage);
+				}
+			}
+			else
+			{
+				Success = false;
+			}
+		}
+		else if (AcceptType != ClientResultValue.Value.GetContentType() && AcceptType != ZenContentType::kUnknownContentType &&
+				 AcceptType != ZenContentType::kBinary)
+		{
+			Success = false;
+		}
+	}
+
+	if (Success)
+	{
+		ZEN_DEBUG("GETCACHERECORD HIT - '{}/{}/{}' {} '{}' (LOCAL) in {}",
+				  Ref.Namespace,
+				  Ref.BucketSegment,
+				  Ref.HashKey,
+				  NiceBytes(ClientResultValue.Value.Size()),
+				  ToString(ClientResultValue.Value.GetContentType()),
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+
+		m_CacheStats.HitCount++;
+		if (SkipData && AcceptType != ZenContentType::kCbPackage && AcceptType != ZenContentType::kCbObject)
+		{
+			return Request.WriteResponse(HttpResponseCode::OK);
+		}
+		else
+		{
+			// kCbPackage handled SkipData when constructing the ClientResultValue, kcbObject ignores SkipData
+			return Request.WriteResponse(HttpResponseCode::OK, ClientResultValue.Value.GetContentType(), ClientResultValue.Value);
+		}
+	}
+	else if (!EnumHasAllFlags(PolicyFromUrl, CachePolicy::QueryRemote))
+	{
+		ZEN_DEBUG("GETCACHERECORD MISS - '{}/{}/{}' '{}' in {}",
+				  Ref.Namespace,
+				  Ref.BucketSegment,
+				  Ref.HashKey,
+				  ToString(AcceptType),
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+		m_CacheStats.MissCount++;
+		return Request.WriteResponse(HttpResponseCode::NotFound);
+	}
+
+	// Issue upstream query asynchronously in order to keep requests flowing without
+	// hogging I/O servicing threads with blocking work
+
+	uint64_t LocalElapsedTimeUs = Timer.GetElapsedTimeUs();
+
+	Request.WriteResponseAsync([this, AcceptType, PolicyFromUrl, Ref, LocalElapsedTimeUs](HttpServerRequest& AsyncRequest) {
+		Stopwatch	  Timer;
+		bool		  Success		= false;
+		const bool	  PartialRecord = EnumHasAllFlags(PolicyFromUrl, CachePolicy::PartialRecord);
+		const bool	  QueryLocal	= EnumHasAllFlags(PolicyFromUrl, CachePolicy::QueryLocal);
+		const bool	  StoreLocal	= EnumHasAllFlags(PolicyFromUrl, CachePolicy::StoreLocal);
+		const bool	  SkipData		= EnumHasAllFlags(PolicyFromUrl, CachePolicy::SkipData);
+		ZenCacheValue ClientResultValue;
+
+		metrics::OperationTiming::Scope $(m_UpstreamGetRequestTiming);
+
+		if (GetUpstreamCacheSingleResult UpstreamResult =
+				m_UpstreamCache.GetCacheRecord(Ref.Namespace, {Ref.BucketSegment, Ref.HashKey}, AcceptType);
+			UpstreamResult.Status.Success)
+		{
+			Success = true;
+
+			ClientResultValue.Value = UpstreamResult.Value;
+			ClientResultValue.Value.SetContentType(AcceptType);
+
+			if (AcceptType == ZenContentType::kBinary || AcceptType == ZenContentType::kCbObject)
+			{
+				if (AcceptType == ZenContentType::kCbObject)
+				{
+					const CbValidateError ValidationResult = ValidateCompactBinary(UpstreamResult.Value, CbValidateMode::All);
+					if (ValidationResult != CbValidateError::None)
+					{
+						Success = false;
+						ZEN_WARN("Get - '{}/{}/{}' '{}' FAILED, invalid compact binary object from upstream",
+								 Ref.Namespace,
+								 Ref.BucketSegment,
+								 Ref.HashKey,
+								 ToString(AcceptType));
+					}
+
+					// We do not do anything to the returned object for SkipData, only package attachments are cut when skipping data
+				}
+
+				if (Success && StoreLocal)
+				{
+					m_CacheStore.Put(Ref.Namespace, Ref.BucketSegment, Ref.HashKey, ClientResultValue);
+				}
+			}
+			else if (AcceptType == ZenContentType::kCbPackage)
+			{
+				CbPackage Package;
+				if (Package.TryLoad(ClientResultValue.Value))
+				{
+					CbObject						 CacheRecord = Package.GetObject();
+					AttachmentCount					 Count;
+					size_t							 NumAttachments = Package.GetAttachments().size();
+					std::vector<const CbAttachment*> AttachmentsToStoreLocally;
+					AttachmentsToStoreLocally.reserve(NumAttachments);
+
+					CacheRecord.IterateAttachments(
+						[this, &Package, &Ref, &AttachmentsToStoreLocally, &Count, QueryLocal, StoreLocal, SkipData](CbFieldView HashView) {
+							IoHash Hash = HashView.AsHash();
+							if (const CbAttachment* Attachment = Package.FindAttachment(Hash))
+							{
+								if (Attachment->IsCompressedBinary())
+								{
+									if (StoreLocal)
+									{
+										AttachmentsToStoreLocally.emplace_back(Attachment);
+									}
+									Count.Valid++;
+								}
+								else
+								{
+									ZEN_WARN("Uncompressed value '{}' from upstream cache record '{}/{}'",
+											 Hash,
+											 Ref.BucketSegment,
+											 Ref.HashKey);
+									Count.Invalid++;
+								}
+							}
+							else if (QueryLocal)
+							{
+								if (SkipData)
+								{
+									if (m_CidStore.ContainsChunk(Hash))
+									{
+										Count.Valid++;
+									}
+								}
+								else if (IoBuffer Chunk = m_CidStore.FindChunkByCid(Hash))
+								{
+									CompressedBuffer Compressed = CompressedBuffer::FromCompressedNoValidate(std::move(Chunk));
+									if (Compressed)
+									{
+										Package.AddAttachment(CbAttachment(Compressed, Hash));
+										Count.Valid++;
+									}
+									else
+									{
+										ZEN_WARN("Uncompressed value '{}' stored in local cache '{}/{}'",
+												 Hash,
+												 Ref.BucketSegment,
+												 Ref.HashKey);
+										Count.Invalid++;
+									}
+								}
+							}
+							Count.Total++;
+						});
+
+					if ((Count.Valid == Count.Total) || PartialRecord)
+					{
+						ZenCacheValue CacheValue;
+						CacheValue.Value = CacheRecord.GetBuffer().AsIoBuffer();
+						CacheValue.Value.SetContentType(ZenContentType::kCbObject);
+
+						if (StoreLocal)
+						{
+							m_CacheStore.Put(Ref.Namespace, Ref.BucketSegment, Ref.HashKey, CacheValue);
+						}
+
+						for (const CbAttachment* Attachment : AttachmentsToStoreLocally)
+						{
+							CompressedBuffer	   Chunk = Attachment->AsCompressedBinary();
+							CidStore::InsertResult InsertResult =
+								m_CidStore.AddChunk(Chunk.GetCompressed().Flatten().AsIoBuffer(), Attachment->GetHash());
+							if (InsertResult.New)
+							{
+								Count.New++;
+							}
+						}
+
+						BinaryWriter MemStream;
+						if (SkipData)
+						{
+							// Save a package containing only the object.
+							CbPackage(Package.GetObject()).Save(MemStream);
+						}
+						else
+						{
+							Package.Save(MemStream);
+						}
+
+						ClientResultValue.Value = IoBuffer(IoBuffer::Clone, MemStream.Data(), MemStream.Size());
+						ClientResultValue.Value.SetContentType(ZenContentType::kCbPackage);
+					}
+					else
+					{
+						Success = false;
+						ZEN_WARN("Get - '{}/{}' '{}' FAILED, attachments missing in upstream package",
+								 Ref.BucketSegment,
+								 Ref.HashKey,
+								 ToString(AcceptType));
+					}
+				}
+				else
+				{
+					Success = false;
+					ZEN_WARN("Get - '{}/{}/{}' '{}' FAILED, invalid upstream package",
+							 Ref.Namespace,
+							 Ref.BucketSegment,
+							 Ref.HashKey,
+							 ToString(AcceptType));
+				}
+			}
+		}
+
+		if (Success)
+		{
+			ZEN_DEBUG("GETCACHERECORD HIT - '{}/{}/{}' {} '{}' (UPSTREAM) in {}",
+					  Ref.Namespace,
+					  Ref.BucketSegment,
+					  Ref.HashKey,
+					  NiceBytes(ClientResultValue.Value.Size()),
+					  ToString(ClientResultValue.Value.GetContentType()),
+					  NiceLatencyNs((LocalElapsedTimeUs + Timer.GetElapsedTimeUs()) * 1000));
+
+			m_CacheStats.HitCount++;
+			m_CacheStats.UpstreamHitCount++;
+
+			if (SkipData && AcceptType == ZenContentType::kBinary)
+			{
+				AsyncRequest.WriteResponse(HttpResponseCode::OK);
+			}
+			else
+			{
+				// Other methods modify ClientResultValue to a version that has skipped the data but keeps the Object and optionally
+				// metadata.
+				AsyncRequest.WriteResponse(HttpResponseCode::OK, ClientResultValue.Value.GetContentType(), ClientResultValue.Value);
+			}
+		}
+		else
+		{
+			ZEN_DEBUG("GETCACHERECORD MISS - '{}/{}/{}' '{}' in {}",
+					  Ref.Namespace,
+					  Ref.BucketSegment,
+					  Ref.HashKey,
+					  ToString(AcceptType),
+					  NiceLatencyNs((LocalElapsedTimeUs + Timer.GetElapsedTimeUs()) * 1000));
+			m_CacheStats.MissCount++;
+			AsyncRequest.WriteResponse(HttpResponseCode::NotFound);
+		}
+	});
+}
+
+void
+HttpStructuredCacheService::HandlePutCacheRecord(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl)
+{
+	IoBuffer Body = Request.ReadPayload();
+
+	if (!Body || Body.Size() == 0)
+	{
+		return Request.WriteResponse(HttpResponseCode::BadRequest);
+	}
+
+	const HttpContentType ContentType = Request.RequestContentType();
+
+	Body.SetContentType(ContentType);
+
+	Stopwatch Timer;
+
+	if (ContentType == HttpContentType::kBinary || ContentType == HttpContentType::kCompressedBinary)
+	{
+		IoHash	 RawHash = IoHash::Zero;
+		uint64_t RawSize = Body.GetSize();
+		if (ContentType == HttpContentType::kCompressedBinary)
+		{
+			if (!CompressedBuffer::ValidateCompressedHeader(Body, RawHash, RawSize))
+			{
+				return Request.WriteResponse(HttpResponseCode::BadRequest,
+											 HttpContentType::kText,
+											 "Payload is not a valid compressed binary"sv);
+			}
+		}
+		else
+		{
+			RawHash = IoHash::HashBuffer(SharedBuffer(Body));
+		}
+		m_CacheStore.Put(Ref.Namespace, Ref.BucketSegment, Ref.HashKey, {.Value = Body, .RawSize = RawSize, .RawHash = RawHash});
+
+		if (EnumHasAllFlags(PolicyFromUrl, CachePolicy::StoreRemote))
+		{
+			m_UpstreamCache.EnqueueUpstream({.Type = ContentType, .Namespace = Ref.Namespace, .Key = {Ref.BucketSegment, Ref.HashKey}});
+		}
+
+		ZEN_DEBUG("PUTCACHERECORD - '{}/{}/{}' {} '{}' in {}",
+				  Ref.Namespace,
+				  Ref.BucketSegment,
+				  Ref.HashKey,
+				  NiceBytes(Body.Size()),
+				  ToString(ContentType),
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+		Request.WriteResponse(HttpResponseCode::Created);
+	}
+	else if (ContentType == HttpContentType::kCbObject)
+	{
+		const CbValidateError ValidationResult = ValidateCompactBinary(MemoryView(Body.GetData(), Body.GetSize()), CbValidateMode::All);
+
+		if (ValidationResult != CbValidateError::None)
+		{
+			ZEN_WARN("PUTCACHERECORD - '{}/{}/{}' '{}' FAILED, invalid compact binary",
+					 Ref.Namespace,
+					 Ref.BucketSegment,
+					 Ref.HashKey,
+					 ToString(ContentType));
+			return Request.WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, "Compact binary validation failed"sv);
+		}
+
+		Body.SetContentType(ZenContentType::kCbObject);
+		m_CacheStore.Put(Ref.Namespace, Ref.BucketSegment, Ref.HashKey, {.Value = Body});
+
+		CbObjectView		CacheRecord(Body.Data());
+		std::vector<IoHash> ValidAttachments;
+		int32_t				TotalCount = 0;
+
+		CacheRecord.IterateAttachments([this, &TotalCount, &ValidAttachments](CbFieldView AttachmentHash) {
+			const IoHash Hash = AttachmentHash.AsHash();
+			if (m_CidStore.ContainsChunk(Hash))
+			{
+				ValidAttachments.emplace_back(Hash);
+			}
+			TotalCount++;
+		});
+
+		ZEN_DEBUG("PUTCACHERECORD - '{}/{}/{}' {} '{}' attachments '{}/{}' (valid/total) in {}",
+				  Ref.Namespace,
+				  Ref.BucketSegment,
+				  Ref.HashKey,
+				  NiceBytes(Body.Size()),
+				  ToString(ContentType),
+				  TotalCount,
+				  ValidAttachments.size(),
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+
+		const bool IsPartialRecord = TotalCount != static_cast<int32_t>(ValidAttachments.size());
+
+		CachePolicy Policy = PolicyFromUrl;
+		if (EnumHasAllFlags(Policy, CachePolicy::StoreRemote) && !IsPartialRecord)
+		{
+			m_UpstreamCache.EnqueueUpstream({.Type			  = ZenContentType::kCbObject,
+											 .Namespace		  = Ref.Namespace,
+											 .Key			  = {Ref.BucketSegment, Ref.HashKey},
+											 .ValueContentIds = std::move(ValidAttachments)});
+		}
+
+		Request.WriteResponse(HttpResponseCode::Created);
+	}
+	else if (ContentType == HttpContentType::kCbPackage)
+	{
+		CbPackage Package;
+
+		if (!Package.TryLoad(Body))
+		{
+			ZEN_WARN("PUTCACHERECORD - '{}/{}/{}' '{}' FAILED, invalid package",
+					 Ref.Namespace,
+					 Ref.BucketSegment,
+					 Ref.HashKey,
+					 ToString(ContentType));
+			return Request.WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, "Invalid package"sv);
+		}
+		CachePolicy Policy = PolicyFromUrl;
+
+		CbObject CacheRecord = Package.GetObject();
+
+		AttachmentCount					 Count;
+		size_t							 NumAttachments = Package.GetAttachments().size();
+		std::vector<IoHash>				 ValidAttachments;
+		std::vector<const CbAttachment*> AttachmentsToStoreLocally;
+		ValidAttachments.reserve(NumAttachments);
+		AttachmentsToStoreLocally.reserve(NumAttachments);
+
+		CacheRecord.IterateAttachments([this, &Ref, &Package, &AttachmentsToStoreLocally, &ValidAttachments, &Count](CbFieldView HashView) {
+			const IoHash Hash = HashView.AsHash();
+			if (const CbAttachment* Attachment = Package.FindAttachment(Hash))
+			{
+				if (Attachment->IsCompressedBinary())
+				{
+					AttachmentsToStoreLocally.emplace_back(Attachment);
+					ValidAttachments.emplace_back(Hash);
+					Count.Valid++;
+				}
+				else
+				{
+					ZEN_WARN("PUTCACHERECORD - '{}/{}/{}' '{}' FAILED, attachment '{}' is not compressed",
+							 Ref.Namespace,
+							 Ref.BucketSegment,
+							 Ref.HashKey,
+							 ToString(HttpContentType::kCbPackage),
+							 Hash);
+					Count.Invalid++;
+				}
+			}
+			else if (m_CidStore.ContainsChunk(Hash))
+			{
+				ValidAttachments.emplace_back(Hash);
+				Count.Valid++;
+			}
+			Count.Total++;
+		});
+
+		if (Count.Invalid > 0)
+		{
+			return Request.WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, "Invalid attachment(s)"sv);
+		}
+
+		ZenCacheValue CacheValue;
+		CacheValue.Value = CacheRecord.GetBuffer().AsIoBuffer();
+		CacheValue.Value.SetContentType(ZenContentType::kCbObject);
+		m_CacheStore.Put(Ref.Namespace, Ref.BucketSegment, Ref.HashKey, CacheValue);
+
+		for (const CbAttachment* Attachment : AttachmentsToStoreLocally)
+		{
+			CompressedBuffer	   Chunk		= Attachment->AsCompressedBinary();
+			CidStore::InsertResult InsertResult = m_CidStore.AddChunk(Chunk.GetCompressed().Flatten().AsIoBuffer(), Attachment->GetHash());
+			if (InsertResult.New)
+			{
+				Count.New++;
+			}
+		}
+
+		ZEN_DEBUG("PUTCACHERECORD - '{}/{}/{}' {} '{}', attachments '{}/{}/{}' (new/valid/total) in {}",
+				  Ref.Namespace,
+				  Ref.BucketSegment,
+				  Ref.HashKey,
+				  NiceBytes(Body.GetSize()),
+				  ToString(ContentType),
+				  Count.New,
+				  Count.Valid,
+				  Count.Total,
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+
+		const bool IsPartialRecord = Count.Valid != Count.Total;
+
+		if (EnumHasAllFlags(Policy, CachePolicy::StoreRemote) && !IsPartialRecord)
+		{
+			m_UpstreamCache.EnqueueUpstream({.Type			  = ZenContentType::kCbPackage,
+											 .Namespace		  = Ref.Namespace,
+											 .Key			  = {Ref.BucketSegment, Ref.HashKey},
+											 .ValueContentIds = std::move(ValidAttachments)});
+		}
+
+		Request.WriteResponse(HttpResponseCode::Created);
+	}
+	else
+	{
+		return Request.WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, "Content-Type invalid"sv);
+	}
+}
+
+void
+HttpStructuredCacheService::HandleCacheChunkRequest(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl)
+{
+	switch (Request.RequestVerb())
+	{
+		case HttpVerb::kHead:
+		case HttpVerb::kGet:
+			HandleGetCacheChunk(Request, Ref, PolicyFromUrl);
+			break;
+		case HttpVerb::kPut:
+			HandlePutCacheChunk(Request, Ref, PolicyFromUrl);
+			break;
+		default:
+			break;
+	}
+}
+
+void
+HttpStructuredCacheService::HandleGetCacheChunk(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl)
+{
+	Stopwatch Timer;
+
+	IoBuffer					Value  = m_CidStore.FindChunkByCid(Ref.ValueContentId);
+	const UpstreamEndpointInfo* Source = nullptr;
+	CachePolicy					Policy = PolicyFromUrl;
+	{
+		const bool QueryUpstream = !Value && EnumHasAllFlags(Policy, CachePolicy::QueryRemote);
+
+		if (QueryUpstream)
+		{
+			if (GetUpstreamCacheSingleResult UpstreamResult =
+					m_UpstreamCache.GetCacheChunk(Ref.Namespace, {Ref.BucketSegment, Ref.HashKey}, Ref.ValueContentId);
+				UpstreamResult.Status.Success)
+			{
+				IoHash	 RawHash;
+				uint64_t RawSize;
+				if (CompressedBuffer::ValidateCompressedHeader(UpstreamResult.Value, RawHash, RawSize))
+				{
+					if (RawHash == Ref.ValueContentId)
+					{
+						m_CidStore.AddChunk(UpstreamResult.Value, RawHash);
+						Source = UpstreamResult.Source;
+					}
+					else
+					{
+						ZEN_WARN("got missmatching upstream cache value");
+					}
+				}
+				else
+				{
+					ZEN_WARN("got uncompressed upstream cache value");
+				}
+			}
+		}
+	}
+
+	if (!Value)
+	{
+		ZEN_DEBUG("GETCACHECHUNK MISS - '{}/{}/{}/{}' '{}' in {}",
+				  Ref.Namespace,
+				  Ref.BucketSegment,
+				  Ref.HashKey,
+				  Ref.ValueContentId,
+				  ToString(Request.AcceptContentType()),
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+		m_CacheStats.MissCount++;
+		return Request.WriteResponse(HttpResponseCode::NotFound);
+	}
+
+	ZEN_DEBUG("GETCACHECHUNK HIT - '{}/{}/{}/{}' {} '{}' ({}) in {}",
+			  Ref.Namespace,
+			  Ref.BucketSegment,
+			  Ref.HashKey,
+			  Ref.ValueContentId,
+			  NiceBytes(Value.Size()),
+			  ToString(Value.GetContentType()),
+			  Source ? Source->Url : "LOCAL"sv,
+			  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+
+	m_CacheStats.HitCount++;
+	if (Source)
+	{
+		m_CacheStats.UpstreamHitCount++;
+	}
+
+	if (EnumHasAllFlags(Policy, CachePolicy::SkipData))
+	{
+		Request.WriteResponse(HttpResponseCode::OK);
+	}
+	else
+	{
+		Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kBinary, Value);
+	}
+}
+
+void
+HttpStructuredCacheService::HandlePutCacheChunk(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl)
+{
+	// Note: Individual cacherecord values are not propagated upstream until a valid cache record has been stored
+	ZEN_UNUSED(PolicyFromUrl);
+
+	Stopwatch Timer;
+
+	IoBuffer Body = Request.ReadPayload();
+
+	if (!Body || Body.Size() == 0)
+	{
+		return Request.WriteResponse(HttpResponseCode::BadRequest);
+	}
+
+	Body.SetContentType(Request.RequestContentType());
+
+	IoHash	 RawHash;
+	uint64_t RawSize;
+	if (!CompressedBuffer::ValidateCompressedHeader(Body, RawHash, RawSize))
+	{
+		return Request.WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, "Attachments must be compressed"sv);
+	}
+
+	if (RawHash != Ref.ValueContentId)
+	{
+		return Request.WriteResponse(HttpResponseCode::BadRequest,
+									 HttpContentType::kText,
+									 "ValueContentId does not match attachment hash"sv);
+	}
+
+	CidStore::InsertResult Result = m_CidStore.AddChunk(Body, RawHash);
+
+	ZEN_DEBUG("PUTCACHECHUNK - '{}/{}/{}/{}' {} '{}' ({}) in {}",
+			  Ref.Namespace,
+			  Ref.BucketSegment,
+			  Ref.HashKey,
+			  Ref.ValueContentId,
+			  NiceBytes(Body.Size()),
+			  ToString(Body.GetContentType()),
+			  Result.New ? "NEW" : "OLD",
+			  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+
+	const HttpResponseCode ResponseCode = Result.New ? HttpResponseCode::Created : HttpResponseCode::OK;
+
+	Request.WriteResponse(ResponseCode);
+}
+
+CbPackage
+HttpStructuredCacheService::HandleRpcRequest(const ZenContentType ContentType,
+											 IoBuffer&&			  Body,
+											 uint32_t&			  OutAcceptMagic,
+											 RpcAcceptOptions&	  OutAcceptFlags,
+											 int&				  OutTargetProcessId)
+{
+	CbPackage	 Package;
+	CbObjectView Object;
+	CbObject	 ObjectBuffer;
+	if (ContentType == ZenContentType::kCbObject)
+	{
+		ObjectBuffer = LoadCompactBinaryObject(std::move(Body));
+		Object		 = ObjectBuffer;
+	}
+	else
+	{
+		Package = ParsePackageMessage(Body);
+		Object	= Package.GetObject();
+	}
+	OutAcceptMagic	   = Object["Accept"sv].AsUInt32();
+	OutAcceptFlags	   = static_cast<RpcAcceptOptions>(Object["AcceptFlags"sv].AsUInt16(0u));
+	OutTargetProcessId = Object["Pid"sv].AsInt32(0);
+
+	const std::string_view Method = Object["Method"sv].AsString();
+
+	if (Method == "PutCacheRecords"sv)
+	{
+		return HandleRpcPutCacheRecords(Package);
+	}
+	else if (Method == "GetCacheRecords"sv)
+	{
+		return HandleRpcGetCacheRecords(Object);
+	}
+	else if (Method == "PutCacheValues"sv)
+	{
+		return HandleRpcPutCacheValues(Package);
+	}
+	else if (Method == "GetCacheValues"sv)
+	{
+		return HandleRpcGetCacheValues(Object);
+	}
+	else if (Method == "GetCacheChunks"sv)
+	{
+		return HandleRpcGetCacheChunks(Object);
+	}
+	return CbPackage{};
+}
+
+void
+HttpStructuredCacheService::ReplayRequestRecorder(cache::IRpcRequestReplayer& Replayer, uint32_t ThreadCount)
+{
+	WorkerThreadPool WorkerPool(ThreadCount);
+	uint64_t		 RequestCount = Replayer.GetRequestCount();
+	Stopwatch		 Timer;
+	auto  _ = MakeGuard([&]() { ZEN_INFO("Replayed {} requests in {}", RequestCount, NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000)); });
+	Latch JobLatch(RequestCount);
+	ZEN_INFO("Replaying {} requests", RequestCount);
+	for (uint64_t RequestIndex = 0; RequestIndex < RequestCount; ++RequestIndex)
+	{
+		WorkerPool.ScheduleWork([this, &JobLatch, &Replayer, RequestIndex]() {
+			IoBuffer								  Body;
+			std::pair<ZenContentType, ZenContentType> ContentType = Replayer.GetRequest(RequestIndex, Body);
+			if (Body)
+			{
+				uint32_t		 AcceptMagic = 0;
+				RpcAcceptOptions AcceptFlags = RpcAcceptOptions::kNone;
+				int				 TargetPid	 = 0;
+				CbPackage		 RpcResult	 = HandleRpcRequest(ContentType.first, std::move(Body), AcceptMagic, AcceptFlags, TargetPid);
+				if (AcceptMagic == kCbPkgMagic)
+				{
+					FormatFlags Flags = FormatFlags::kDefault;
+					if (EnumHasAllFlags(AcceptFlags, RpcAcceptOptions::kAllowLocalReferences))
+					{
+						Flags |= FormatFlags::kAllowLocalReferences;
+						if (!EnumHasAnyFlags(AcceptFlags, RpcAcceptOptions::kAllowPartialLocalReferences))
+						{
+							Flags |= FormatFlags::kDenyPartialLocalReferences;
+						}
+					}
+					CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResult, Flags, TargetPid);
+					ZEN_ASSERT(RpcResponseBuffer.GetSize() > 0);
+				}
+				else
+				{
+					BinaryWriter MemStream;
+					RpcResult.Save(MemStream);
+					IoBuffer RpcResponseBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize());
+					ZEN_ASSERT(RpcResponseBuffer.Size() > 0);
+				}
+			}
+			JobLatch.CountDown();
+		});
+	}
+	while (!JobLatch.Wait(10000))
+	{
+		ZEN_INFO("Replayed {} of {} requests, elapsed {}",
+				 RequestCount - JobLatch.Remaining(),
+				 RequestCount,
+				 NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+	}
+}
+
+void
+HttpStructuredCacheService::HandleRpcRequest(HttpServerRequest& Request)
+{
+	switch (Request.RequestVerb())
+	{
+		case HttpVerb::kPost:
+			{
+				const HttpContentType ContentType = Request.RequestContentType();
+				const HttpContentType AcceptType  = Request.AcceptContentType();
+
+				if ((ContentType != HttpContentType::kCbObject && ContentType != HttpContentType::kCbPackage) ||
+					AcceptType != HttpContentType::kCbPackage)
+				{
+					return Request.WriteResponse(HttpResponseCode::BadRequest);
+				}
+
+				Request.WriteResponseAsync(
+					[this, Body = Request.ReadPayload(), ContentType, AcceptType](HttpServerRequest& AsyncRequest) mutable {
+						std::uint64_t RequestIndex =
+							m_RequestRecorder ? m_RequestRecorder->RecordRequest(ContentType, AcceptType, Body) : ~0ull;
+						uint32_t		 AcceptMagic	 = 0;
+						RpcAcceptOptions AcceptFlags	 = RpcAcceptOptions::kNone;
+						int				 TargetProcessId = 0;
+						CbPackage RpcResult = HandleRpcRequest(ContentType, std::move(Body), AcceptMagic, AcceptFlags, TargetProcessId);
+						if (RpcResult.IsNull())
+						{
+							AsyncRequest.WriteResponse(HttpResponseCode::BadRequest);
+							return;
+						}
+						if (AcceptMagic == kCbPkgMagic)
+						{
+							FormatFlags Flags = FormatFlags::kDefault;
+							if (EnumHasAllFlags(AcceptFlags, RpcAcceptOptions::kAllowLocalReferences))
+							{
+								Flags |= FormatFlags::kAllowLocalReferences;
+								if (!EnumHasAnyFlags(AcceptFlags, RpcAcceptOptions::kAllowPartialLocalReferences))
+								{
+									Flags |= FormatFlags::kDenyPartialLocalReferences;
+								}
+							}
+							CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResult, Flags, TargetProcessId);
+							if (RequestIndex != ~0ull)
+							{
+								ZEN_ASSERT(m_RequestRecorder);
+								m_RequestRecorder->RecordResponse(RequestIndex, HttpContentType::kCbPackage, RpcResponseBuffer);
+							}
+							AsyncRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+						}
+						else
+						{
+							BinaryWriter MemStream;
+							RpcResult.Save(MemStream);
+
+							if (RequestIndex != ~0ull)
+							{
+								ZEN_ASSERT(m_RequestRecorder);
+								m_RequestRecorder->RecordResponse(RequestIndex,
+																  HttpContentType::kCbPackage,
+																  IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+							}
+							AsyncRequest.WriteResponse(HttpResponseCode::OK,
+													   HttpContentType::kCbPackage,
+													   IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+						}
+					});
+			}
+			break;
+		default:
+			Request.WriteResponse(HttpResponseCode::BadRequest);
+			break;
+	}
+}
+
+CbPackage
+HttpStructuredCacheService::HandleRpcPutCacheRecords(const CbPackage& BatchRequest)
+{
+	ZEN_TRACE_CPU("Z$::RpcPutCacheRecords");
+	CbObjectView BatchObject = BatchRequest.GetObject();
+	ZEN_ASSERT(BatchObject["Method"sv].AsString() == "PutCacheRecords"sv);
+
+	CbObjectView Params = BatchObject["Params"sv].AsObjectView();
+	CachePolicy	 DefaultPolicy;
+
+	std::string_view		   PolicyText = Params["DefaultPolicy"].AsString();
+	std::optional<std::string> Namespace  = GetRpcRequestNamespace(Params);
+	if (!Namespace)
+	{
+		return CbPackage{};
+	}
+	DefaultPolicy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : CachePolicy::Default;
+	std::vector<bool> Results;
+	for (CbFieldView RequestField : Params["Requests"sv])
+	{
+		CbObjectView RequestObject = RequestField.AsObjectView();
+		CbObjectView RecordObject  = RequestObject["Record"sv].AsObjectView();
+		CbObjectView KeyView	   = RecordObject["Key"sv].AsObjectView();
+
+		CacheKey Key;
+		if (!GetRpcRequestCacheKey(KeyView, Key))
+		{
+			return CbPackage{};
+		}
+		CacheRecordPolicy Policy = LoadCacheRecordPolicy(RequestObject["Policy"sv].AsObjectView(), DefaultPolicy);
+		PutRequestData	  PutRequest{*Namespace, std::move(Key), RecordObject, std::move(Policy)};
+
+		PutResult Result = PutCacheRecord(PutRequest, &BatchRequest);
+
+		if (Result == PutResult::Invalid)
+		{
+			return CbPackage{};
+		}
+		Results.push_back(Result == PutResult::Success);
+	}
+	if (Results.empty())
+	{
+		return CbPackage{};
+	}
+
+	CbObjectWriter ResponseObject;
+	ResponseObject.BeginArray("Result"sv);
+	for (bool Value : Results)
+	{
+		ResponseObject.AddBool(Value);
+	}
+	ResponseObject.EndArray();
+
+	CbPackage RpcResponse;
+	RpcResponse.SetObject(ResponseObject.Save());
+	return RpcResponse;
+}
+
+HttpStructuredCacheService::PutResult
+HttpStructuredCacheService::PutCacheRecord(PutRequestData& Request, const CbPackage* Package)
+{
+	CbObjectView Record			  = Request.RecordObject;
+	uint64_t	 RecordObjectSize = Record.GetSize();
+	uint64_t	 TransferredSize  = RecordObjectSize;
+
+	AttachmentCount					 Count;
+	size_t							 NumAttachments = Package->GetAttachments().size();
+	std::vector<IoHash>				 ValidAttachments;
+	std::vector<const CbAttachment*> AttachmentsToStoreLocally;
+	ValidAttachments.reserve(NumAttachments);
+	AttachmentsToStoreLocally.reserve(NumAttachments);
+
+	Stopwatch Timer;
+
+	Request.RecordObject.IterateAttachments(
+		[this, &Request, Package, &AttachmentsToStoreLocally, &ValidAttachments, &Count, &TransferredSize](CbFieldView HashView) {
+			const IoHash ValueHash = HashView.AsHash();
+			if (const CbAttachment* Attachment = Package ? Package->FindAttachment(ValueHash) : nullptr)
+			{
+				if (Attachment->IsCompressedBinary())
+				{
+					AttachmentsToStoreLocally.emplace_back(Attachment);
+					ValidAttachments.emplace_back(ValueHash);
+					Count.Valid++;
+				}
+				else
+				{
+					ZEN_WARN("PUTCACEHRECORD - '{}/{}/{}' '{}' FAILED, attachment '{}' is not compressed",
+							 Request.Namespace,
+							 Request.Key.Bucket,
+							 Request.Key.Hash,
+							 ToString(HttpContentType::kCbPackage),
+							 ValueHash);
+					Count.Invalid++;
+				}
+			}
+			else if (m_CidStore.ContainsChunk(ValueHash))
+			{
+				ValidAttachments.emplace_back(ValueHash);
+				Count.Valid++;
+			}
+			Count.Total++;
+		});
+
+	if (Count.Invalid > 0)
+	{
+		return PutResult::Invalid;
+	}
+
+	ZenCacheValue CacheValue;
+	CacheValue.Value = IoBuffer(Record.GetSize());
+	Record.CopyTo(MutableMemoryView(CacheValue.Value.MutableData(), CacheValue.Value.GetSize()));
+	CacheValue.Value.SetContentType(ZenContentType::kCbObject);
+	m_CacheStore.Put(Request.Namespace, Request.Key.Bucket, Request.Key.Hash, CacheValue);
+
+	for (const CbAttachment* Attachment : AttachmentsToStoreLocally)
+	{
+		CompressedBuffer	   Chunk		= Attachment->AsCompressedBinary();
+		CidStore::InsertResult InsertResult = m_CidStore.AddChunk(Chunk.GetCompressed().Flatten().AsIoBuffer(), Attachment->GetHash());
+		if (InsertResult.New)
+		{
+			Count.New++;
+		}
+		TransferredSize += Chunk.GetCompressedSize();
+	}
+
+	ZEN_DEBUG("PUTCACEHRECORD - '{}/{}/{}' {}, attachments '{}/{}/{}' (new/valid/total) in {}",
+			  Request.Namespace,
+			  Request.Key.Bucket,
+			  Request.Key.Hash,
+			  NiceBytes(TransferredSize),
+			  Count.New,
+			  Count.Valid,
+			  Count.Total,
+			  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+
+	const bool IsPartialRecord = Count.Valid != Count.Total;
+
+	if (EnumHasAllFlags(Request.Policy.GetRecordPolicy(), CachePolicy::StoreRemote) && !IsPartialRecord)
+	{
+		m_UpstreamCache.EnqueueUpstream({.Type			  = ZenContentType::kCbPackage,
+										 .Namespace		  = Request.Namespace,
+										 .Key			  = Request.Key,
+										 .ValueContentIds = std::move(ValidAttachments)});
+	}
+	return PutResult::Success;
+}
+
+CbPackage
+HttpStructuredCacheService::HandleRpcGetCacheRecords(CbObjectView RpcRequest)
+{
+	ZEN_TRACE_CPU("Z$::RpcGetCacheRecords");
+
+	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheRecords"sv);
+
+	CbObjectView Params = RpcRequest["Params"sv].AsObjectView();
+
+	struct ValueRequestData
+	{
+		Oid				 ValueId;
+		IoHash			 ContentId;
+		CompressedBuffer Payload;
+		CachePolicy		 DownstreamPolicy;
+		bool			 Exists			  = false;
+		bool			 ReadFromUpstream = false;
+	};
+	struct RecordRequestData
+	{
+		CacheKeyRequest				  Upstream;
+		CbObjectView				  RecordObject;
+		IoBuffer					  RecordCacheValue;
+		CacheRecordPolicy			  DownstreamPolicy;
+		std::vector<ValueRequestData> Values;
+		bool						  Complete = false;
+		const UpstreamEndpointInfo*	  Source   = nullptr;
+		uint64_t					  ElapsedTimeUs;
+	};
+
+	std::string_view		   PolicyText	 = Params["DefaultPolicy"sv].AsString();
+	CachePolicy				   DefaultPolicy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : CachePolicy::Default;
+	std::optional<std::string> Namespace	 = GetRpcRequestNamespace(Params);
+	if (!Namespace)
+	{
+		return CbPackage{};
+	}
+	std::vector<RecordRequestData> Requests;
+	std::vector<size_t>			   UpstreamIndexes;
+	CbArrayView					   RequestsArray = Params["Requests"sv].AsArrayView();
+	Requests.reserve(RequestsArray.Num());
+
+	auto ParseValues = [](RecordRequestData& Request) {
+		CbArrayView ValuesArray = Request.RecordObject["Values"sv].AsArrayView();
+		Request.Values.reserve(ValuesArray.Num());
+		for (CbFieldView ValueField : ValuesArray)
+		{
+			CbObjectView ValueObject  = ValueField.AsObjectView();
+			Oid			 ValueId	  = ValueObject["Id"sv].AsObjectId();
+			CbFieldView	 RawHashField = ValueObject["RawHash"sv];
+			IoHash		 RawHash	  = RawHashField.AsBinaryAttachment();
+			if (ValueId && !RawHashField.HasError())
+			{
+				Request.Values.push_back({ValueId, RawHash});
+				Request.Values.back().DownstreamPolicy = Request.DownstreamPolicy.GetValuePolicy(ValueId);
+			}
+		}
+	};
+
+	for (CbFieldView RequestField : RequestsArray)
+	{
+		Stopwatch		   Timer;
+		RecordRequestData& Request		 = Requests.emplace_back();
+		CbObjectView	   RequestObject = RequestField.AsObjectView();
+		CbObjectView	   KeyObject	 = RequestObject["Key"sv].AsObjectView();
+
+		CacheKey& Key = Request.Upstream.Key;
+		if (!GetRpcRequestCacheKey(KeyObject, Key))
+		{
+			return CbPackage{};
+		}
+
+		Request.DownstreamPolicy		= LoadCacheRecordPolicy(RequestObject["Policy"sv].AsObjectView(), DefaultPolicy);
+		const CacheRecordPolicy& Policy = Request.DownstreamPolicy;
+
+		ZenCacheValue CacheValue;
+		bool		  NeedUpstreamAttachment = false;
+		bool		  FoundLocalInvalid		 = false;
+		ZenCacheValue RecordCacheValue;
+
+		if (EnumHasAllFlags(Policy.GetRecordPolicy(), CachePolicy::QueryLocal) &&
+			m_CacheStore.Get(*Namespace, Key.Bucket, Key.Hash, RecordCacheValue))
+		{
+			Request.RecordCacheValue = std::move(RecordCacheValue.Value);
+			if (Request.RecordCacheValue.GetContentType() != ZenContentType::kCbObject)
+			{
+				FoundLocalInvalid = true;
+			}
+			else
+			{
+				Request.RecordObject = CbObjectView(Request.RecordCacheValue.GetData());
+				ParseValues(Request);
+
+				Request.Complete = true;
+				for (ValueRequestData& Value : Request.Values)
+				{
+					CachePolicy ValuePolicy = Value.DownstreamPolicy;
+					if (!EnumHasAllFlags(ValuePolicy, CachePolicy::QueryLocal))
+					{
+						// A value that is requested without the Query flag (such as None/Disable) counts as existing, because we
+						// didn't ask for it and thus the record is complete in its absence.
+						if (!EnumHasAllFlags(ValuePolicy, CachePolicy::QueryRemote))
+						{
+							Value.Exists = true;
+						}
+						else
+						{
+							NeedUpstreamAttachment = true;
+							Value.ReadFromUpstream = true;
+							Request.Complete	   = false;
+						}
+					}
+					else if (EnumHasAllFlags(ValuePolicy, CachePolicy::SkipData))
+					{
+						if (m_CidStore.ContainsChunk(Value.ContentId))
+						{
+							Value.Exists = true;
+						}
+						else
+						{
+							if (EnumHasAllFlags(ValuePolicy, CachePolicy::QueryRemote))
+							{
+								NeedUpstreamAttachment = true;
+								Value.ReadFromUpstream = true;
+							}
+							Request.Complete = false;
+						}
+					}
+					else
+					{
+						if (IoBuffer Chunk = m_CidStore.FindChunkByCid(Value.ContentId))
+						{
+							ZEN_ASSERT(Chunk.GetSize() > 0);
+							Value.Payload = CompressedBuffer::FromCompressedNoValidate(std::move(Chunk));
+							Value.Exists  = true;
+						}
+						else
+						{
+							if (EnumHasAllFlags(ValuePolicy, CachePolicy::QueryRemote))
+							{
+								NeedUpstreamAttachment = true;
+								Value.ReadFromUpstream = true;
+							}
+							Request.Complete = false;
+						}
+					}
+				}
+			}
+		}
+		if (!Request.Complete)
+		{
+			bool NeedUpstreamRecord =
+				!Request.RecordObject && !FoundLocalInvalid && EnumHasAllFlags(Policy.GetRecordPolicy(), CachePolicy::QueryRemote);
+			if (NeedUpstreamRecord || NeedUpstreamAttachment)
+			{
+				UpstreamIndexes.push_back(Requests.size() - 1);
+			}
+		}
+		Request.ElapsedTimeUs = Timer.GetElapsedTimeUs();
+	}
+	if (Requests.empty())
+	{
+		return CbPackage{};
+	}
+
+	if (!UpstreamIndexes.empty())
+	{
+		std::vector<CacheKeyRequest*> UpstreamRequests;
+		UpstreamRequests.reserve(UpstreamIndexes.size());
+		for (size_t Index : UpstreamIndexes)
+		{
+			RecordRequestData& Request = Requests[Index];
+			UpstreamRequests.push_back(&Request.Upstream);
+
+			if (Request.Values.size())
+			{
+				// We will be returning the local object and know all the value Ids that exist in it
+				// Convert all their Downstream Values to upstream values, and add SkipData to any ones that we already have.
+				CachePolicy UpstreamBasePolicy = ConvertToUpstream(Request.DownstreamPolicy.GetBasePolicy()) | CachePolicy::SkipMeta;
+				CacheRecordPolicyBuilder Builder(UpstreamBasePolicy);
+				for (ValueRequestData& Value : Request.Values)
+				{
+					CachePolicy UpstreamPolicy = ConvertToUpstream(Value.DownstreamPolicy);
+					UpstreamPolicy |= !Value.ReadFromUpstream ? CachePolicy::SkipData : CachePolicy::None;
+					Builder.AddValuePolicy(Value.ValueId, UpstreamPolicy);
+				}
+				Request.Upstream.Policy = Builder.Build();
+			}
+			else
+			{
+				// We don't know which Values exist in the Record; ask the upstrem for all values that the client wants,
+				// and convert the CacheRecordPolicy to an upstream policy
+				Request.Upstream.Policy = Request.DownstreamPolicy.ConvertToUpstream();
+			}
+		}
+
+		const auto OnCacheRecordGetComplete = [this, Namespace, &ParseValues](CacheRecordGetCompleteParams&& Params) {
+			if (!Params.Record)
+			{
+				return;
+			}
+
+			RecordRequestData& Request =
+				*reinterpret_cast<RecordRequestData*>(reinterpret_cast<char*>(&Params.Request) - offsetof(RecordRequestData, Upstream));
+			Request.ElapsedTimeUs += static_cast<uint64_t>(Params.ElapsedSeconds * 1000000.0);
+			const CacheKey& Key = Request.Upstream.Key;
+			Stopwatch		Timer;
+			auto			TimeGuard = MakeGuard([&Timer, &Request]() { Request.ElapsedTimeUs += Timer.GetElapsedTimeUs(); });
+			if (!Request.RecordObject)
+			{
+				CbObject ObjectBuffer	 = CbObject::Clone(Params.Record);
+				Request.RecordCacheValue = ObjectBuffer.GetBuffer().AsIoBuffer();
+				Request.RecordCacheValue.SetContentType(ZenContentType::kCbObject);
+				Request.RecordObject = ObjectBuffer;
+				if (EnumHasAllFlags(Request.DownstreamPolicy.GetRecordPolicy(), CachePolicy::StoreLocal))
+				{
+					m_CacheStore.Put(*Namespace, Key.Bucket, Key.Hash, {.Value = {Request.RecordCacheValue}});
+				}
+				ParseValues(Request);
+				Request.Source = Params.Source;
+			}
+
+			Request.Complete = true;
+			for (ValueRequestData& Value : Request.Values)
+			{
+				if (Value.Exists)
+				{
+					continue;
+				}
+				CachePolicy ValuePolicy = Value.DownstreamPolicy;
+				if (!EnumHasAllFlags(ValuePolicy, CachePolicy::QueryRemote))
+				{
+					Request.Complete = false;
+					continue;
+				}
+				if (!EnumHasAllFlags(ValuePolicy, CachePolicy::SkipData) || EnumHasAllFlags(ValuePolicy, CachePolicy::StoreLocal))
+				{
+					if (const CbAttachment* Attachment = Params.Package.FindAttachment(Value.ContentId))
+					{
+						if (CompressedBuffer Compressed = Attachment->AsCompressedBinary())
+						{
+							Request.Source = Params.Source;
+							Value.Exists   = true;
+							if (EnumHasAllFlags(ValuePolicy, CachePolicy::StoreLocal))
+							{
+								m_CidStore.AddChunk(Compressed.GetCompressed().Flatten().AsIoBuffer(), Attachment->GetHash());
+							}
+							if (!EnumHasAllFlags(ValuePolicy, CachePolicy::SkipData))
+							{
+								Value.Payload = Compressed;
+							}
+						}
+						else
+						{
+							ZEN_DEBUG("Uncompressed value '{}' from upstream cache record '{}/{}/{}'",
+									  Value.ContentId,
+									  *Namespace,
+									  Key.Bucket,
+									  Key.Hash);
+						}
+					}
+					if (!Value.Exists && !EnumHasAllFlags(ValuePolicy, CachePolicy::SkipData))
+					{
+						Request.Complete = false;
+					}
+					// Request.Complete does not need to be set to false for upstream SkipData attachments.
+					// In the PartialRecord==false case, the upstream will have failed the entire record if any SkipData attachment
+					// didn't exist and we will not get here. In the PartialRecord==true case, we do not need to inform the client of
+					// any missing SkipData attachments.
+				}
+				Request.ElapsedTimeUs += Timer.GetElapsedTimeUs();
+			}
+		};
+
+		m_UpstreamCache.GetCacheRecords(*Namespace, UpstreamRequests, std::move(OnCacheRecordGetComplete));
+	}
+
+	CbPackage	   ResponsePackage;
+	CbObjectWriter ResponseObject;
+
+	ResponseObject.BeginArray("Result"sv);
+	for (RecordRequestData& Request : Requests)
+	{
+		const CacheKey& Key = Request.Upstream.Key;
+		if (Request.Complete ||
+			(Request.RecordObject && EnumHasAllFlags(Request.DownstreamPolicy.GetRecordPolicy(), CachePolicy::PartialRecord)))
+		{
+			ResponseObject << Request.RecordObject;
+			for (ValueRequestData& Value : Request.Values)
+			{
+				if (!EnumHasAllFlags(Value.DownstreamPolicy, CachePolicy::SkipData) && Value.Payload)
+				{
+					ResponsePackage.AddAttachment(CbAttachment(Value.Payload, Value.ContentId));
+				}
+			}
+
+			ZEN_DEBUG("GETCACHERECORD HIT - '{}/{}/{}' {}{} ({}) in {}",
+					  *Namespace,
+					  Key.Bucket,
+					  Key.Hash,
+					  NiceBytes(Request.RecordCacheValue.Size()),
+					  Request.Complete ? ""sv : " (PARTIAL)"sv,
+					  Request.Source ? Request.Source->Url : "LOCAL"sv,
+					  NiceLatencyNs(Request.ElapsedTimeUs * 1000));
+			m_CacheStats.HitCount++;
+			m_CacheStats.UpstreamHitCount += Request.Source ? 1 : 0;
+		}
+		else
+		{
+			ResponseObject.AddNull();
+
+			if (!EnumHasAnyFlags(Request.DownstreamPolicy.GetRecordPolicy(), CachePolicy::Query))
+			{
+				// If they requested no query, do not record this as a miss
+				ZEN_DEBUG("GETCACHERECORD DISABLEDQUERY - '{}/{}/{}' in {}",
+						  *Namespace,
+						  Key.Bucket,
+						  Key.Hash,
+						  NiceLatencyNs(Request.ElapsedTimeUs * 1000));
+			}
+			else
+			{
+				ZEN_DEBUG("GETCACHERECORD MISS - '{}/{}/{}'{} ({}) in {}",
+						  *Namespace,
+						  Key.Bucket,
+						  Key.Hash,
+						  Request.RecordObject ? ""sv : " (PARTIAL)"sv,
+						  Request.Source ? Request.Source->Url : "LOCAL"sv,
+						  NiceLatencyNs(Request.ElapsedTimeUs * 1000));
+				m_CacheStats.MissCount++;
+			}
+		}
+	}
+	ResponseObject.EndArray();
+	ResponsePackage.SetObject(ResponseObject.Save());
+	return ResponsePackage;
+}
+
+CbPackage
+HttpStructuredCacheService::HandleRpcPutCacheValues(const CbPackage& BatchRequest)
+{
+	CbObjectView BatchObject = BatchRequest.GetObject();
+	CbObjectView Params		 = BatchObject["Params"sv].AsObjectView();
+
+	std::string_view		   PolicyText	 = Params["DefaultPolicy"].AsString();
+	CachePolicy				   DefaultPolicy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : CachePolicy::Default;
+	std::optional<std::string> Namespace	 = GetRpcRequestNamespace(Params);
+	if (!Namespace)
+	{
+		return CbPackage{};
+	}
+	std::vector<bool> Results;
+	for (CbFieldView RequestField : Params["Requests"sv])
+	{
+		Stopwatch Timer;
+
+		CbObjectView RequestObject = RequestField.AsObjectView();
+		CbObjectView KeyView	   = RequestObject["Key"sv].AsObjectView();
+
+		CacheKey Key;
+		if (!GetRpcRequestCacheKey(KeyView, Key))
+		{
+			return CbPackage{};
+		}
+
+		PolicyText					= RequestObject["Policy"sv].AsString();
+		CachePolicy Policy			= !PolicyText.empty() ? ParseCachePolicy(PolicyText) : DefaultPolicy;
+		IoHash		RawHash			= RequestObject["RawHash"sv].AsBinaryAttachment();
+		uint64_t	RawSize			= RequestObject["RawSize"sv].AsUInt64();
+		bool		Succeeded		= false;
+		uint64_t	TransferredSize = 0;
+
+		if (const CbAttachment* Attachment = BatchRequest.FindAttachment(RawHash))
+		{
+			if (Attachment->IsCompressedBinary())
+			{
+				CompressedBuffer Chunk = Attachment->AsCompressedBinary();
+				if (EnumHasAllFlags(Policy, CachePolicy::StoreRemote))
+				{
+					// TODO: Implement upstream puts of CacheValues with StoreLocal == false.
+					// Currently ProcessCacheRecord requires that the value exist in the local cache to put it upstream.
+					Policy |= CachePolicy::StoreLocal;
+				}
+
+				if (EnumHasAllFlags(Policy, CachePolicy::StoreLocal))
+				{
+					IoBuffer Value = Chunk.GetCompressed().Flatten().AsIoBuffer();
+					Value.SetContentType(ZenContentType::kCompressedBinary);
+					if (RawSize == 0)
+					{
+						RawSize = Chunk.DecodeRawSize();
+					}
+					m_CacheStore.Put(*Namespace, Key.Bucket, Key.Hash, {.Value = Value, .RawSize = RawSize, .RawHash = RawHash});
+					TransferredSize = Chunk.GetCompressedSize();
+				}
+				Succeeded = true;
+			}
+			else
+			{
+				ZEN_WARN("PUTCACHEVALUES - '{}/{}/{}/{}' FAILED, value is not compressed", *Namespace, Key.Bucket, Key.Hash, RawHash);
+				return CbPackage{};
+			}
+		}
+		else if (EnumHasAllFlags(Policy, CachePolicy::QueryLocal))
+		{
+			ZenCacheValue ExistingValue;
+			if (m_CacheStore.Get(*Namespace, Key.Bucket, Key.Hash, ExistingValue) &&
+				IsCompressedBinary(ExistingValue.Value.GetContentType()))
+			{
+				Succeeded = true;
+			}
+		}
+		// We do not search the Upstream. No data in a put means the caller is probing for whether they need to do a heavy put.
+		// If it doesn't exist locally they should do the heavy put rather than having us fetch it from upstream.
+
+		if (Succeeded && EnumHasAllFlags(Policy, CachePolicy::StoreRemote))
+		{
+			m_UpstreamCache.EnqueueUpstream({.Type = ZenContentType::kCompressedBinary, .Namespace = *Namespace, .Key = Key});
+		}
+		Results.push_back(Succeeded);
+		ZEN_DEBUG("PUTCACHEVALUES - '{}/{}/{}' {}, '{}' in {}",
+				  *Namespace,
+				  Key.Bucket,
+				  Key.Hash,
+				  NiceBytes(TransferredSize),
+				  Succeeded ? "Added"sv : "Invalid",
+				  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+	}
+	if (Results.empty())
+	{
+		return CbPackage{};
+	}
+
+	CbObjectWriter ResponseObject;
+	ResponseObject.BeginArray("Result"sv);
+	for (bool Value : Results)
+	{
+		ResponseObject.AddBool(Value);
+	}
+	ResponseObject.EndArray();
+
+	CbPackage RpcResponse;
+	RpcResponse.SetObject(ResponseObject.Save());
+
+	return RpcResponse;
+}
+
+CbPackage
+HttpStructuredCacheService::HandleRpcGetCacheValues(CbObjectView RpcRequest)
+{
+	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheValues"sv);
+
+	CbObjectView			   Params		 = RpcRequest["Params"sv].AsObjectView();
+	std::string_view		   PolicyText	 = Params["DefaultPolicy"sv].AsString();
+	CachePolicy				   DefaultPolicy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : CachePolicy::Default;
+	std::optional<std::string> Namespace	 = GetRpcRequestNamespace(Params);
+	if (!Namespace)
+	{
+		return CbPackage{};
+	}
+
+	struct RequestData
+	{
+		CacheKey		 Key;
+		CachePolicy		 Policy;
+		IoHash			 RawHash = IoHash::Zero;
+		uint64_t		 RawSize = 0;
+		CompressedBuffer Result;
+	};
+	std::vector<RequestData> Requests;
+
+	std::vector<size_t> RemoteRequestIndexes;
+
+	for (CbFieldView RequestField : Params["Requests"sv])
+	{
+		Stopwatch Timer;
+
+		RequestData& Request	   = Requests.emplace_back();
+		CbObjectView RequestObject = RequestField.AsObjectView();
+		CbObjectView KeyObject	   = RequestObject["Key"sv].AsObjectView();
+
+		if (!GetRpcRequestCacheKey(KeyObject, Request.Key))
+		{
+			return CbPackage{};
+		}
+
+		PolicyText	   = RequestObject["Policy"sv].AsString();
+		Request.Policy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : DefaultPolicy;
+
+		CacheKey&	Key	   = Request.Key;
+		CachePolicy Policy = Request.Policy;
+
+		ZenCacheValue CacheValue;
+		if (EnumHasAllFlags(Policy, CachePolicy::QueryLocal))
+		{
+			if (m_CacheStore.Get(*Namespace, Key.Bucket, Key.Hash, CacheValue) && IsCompressedBinary(CacheValue.Value.GetContentType()))
+			{
+				Request.RawHash = CacheValue.RawHash;
+				Request.RawSize = CacheValue.RawSize;
+				Request.Result	= CompressedBuffer::FromCompressedNoValidate(std::move(CacheValue.Value));
+			}
+		}
+		if (Request.Result)
+		{
+			ZEN_DEBUG("GETCACHEVALUES HIT - '{}/{}/{}' {} ({}) in {}",
+					  *Namespace,
+					  Key.Bucket,
+					  Key.Hash,
+					  NiceBytes(Request.Result.GetCompressed().GetSize()),
+					  "LOCAL"sv,
+					  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+			m_CacheStats.HitCount++;
+		}
+		else if (EnumHasAllFlags(Policy, CachePolicy::QueryRemote))
+		{
+			RemoteRequestIndexes.push_back(Requests.size() - 1);
+		}
+		else if (!EnumHasAnyFlags(Policy, CachePolicy::Query))
+		{
+			// If they requested no query, do not record this as a miss
+			ZEN_DEBUG("GETCACHEVALUES DISABLEDQUERY - '{}/{}/{}'", *Namespace, Key.Bucket, Key.Hash);
+		}
+		else
+		{
+			ZEN_DEBUG("GETCACHEVALUES MISS - '{}/{}/{}' ({}) in {}",
+					  *Namespace,
+					  Key.Bucket,
+					  Key.Hash,
+					  "LOCAL"sv,
+					  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+			m_CacheStats.MissCount++;
+		}
+	}
+
+	if (!RemoteRequestIndexes.empty())
+	{
+		std::vector<CacheValueRequest>	RequestedRecordsData;
+		std::vector<CacheValueRequest*> CacheValueRequests;
+		RequestedRecordsData.reserve(RemoteRequestIndexes.size());
+		CacheValueRequests.reserve(RemoteRequestIndexes.size());
+		for (size_t Index : RemoteRequestIndexes)
+		{
+			RequestData& Request = Requests[Index];
+			RequestedRecordsData.push_back({.Key = {Request.Key.Bucket, Request.Key.Hash}, .Policy = ConvertToUpstream(Request.Policy)});
+			CacheValueRequests.push_back(&RequestedRecordsData.back());
+		}
+		Stopwatch Timer;
+		m_UpstreamCache.GetCacheValues(
+			*Namespace,
+			CacheValueRequests,
+			[this, Namespace, &RequestedRecordsData, &Requests, &RemoteRequestIndexes, &Timer](CacheValueGetCompleteParams&& Params) {
+				CacheValueRequest& ChunkRequest = Params.Request;
+				if (Params.RawHash != IoHash::Zero)
+				{
+					size_t		 RequestOffset = std::distance(RequestedRecordsData.data(), &ChunkRequest);
+					size_t		 RequestIndex  = RemoteRequestIndexes[RequestOffset];
+					RequestData& Request	   = Requests[RequestIndex];
+					Request.RawHash			   = Params.RawHash;
+					Request.RawSize			   = Params.RawSize;
+					const bool HasData		   = IsCompressedBinary(Params.Value.GetContentType());
+					const bool SkipData		   = EnumHasAllFlags(Request.Policy, CachePolicy::SkipData);
+					const bool StoreData	   = EnumHasAllFlags(Request.Policy, CachePolicy::StoreLocal);
+					const bool IsHit		   = SkipData || HasData;
+					if (IsHit)
+					{
+						if (HasData && !SkipData)
+						{
+							Request.Result = CompressedBuffer::FromCompressedNoValidate(IoBuffer(Params.Value));
+						}
+
+						if (HasData && StoreData)
+						{
+							m_CacheStore.Put(*Namespace,
+											 Request.Key.Bucket,
+											 Request.Key.Hash,
+											 ZenCacheValue{.Value = Params.Value, .RawSize = Request.RawSize, .RawHash = Request.RawHash});
+						}
+
+						ZEN_DEBUG("GETCACHEVALUES HIT - '{}/{}/{}' {} ({}) in {}",
+								  *Namespace,
+								  ChunkRequest.Key.Bucket,
+								  ChunkRequest.Key.Hash,
+								  NiceBytes(Request.Result.GetCompressed().GetSize()),
+								  Params.Source ? Params.Source->Url : "UPSTREAM",
+								  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+						m_CacheStats.HitCount++;
+						m_CacheStats.UpstreamHitCount++;
+						return;
+					}
+				}
+				ZEN_DEBUG("GETCACHEVALUES MISS - '{}/{}/{}' ({}) in {}",
+						  *Namespace,
+						  ChunkRequest.Key.Bucket,
+						  ChunkRequest.Key.Hash,
+						  Params.Source ? Params.Source->Url : "UPSTREAM",
+						  NiceLatencyNs(Timer.GetElapsedTimeUs() * 1000));
+				m_CacheStats.MissCount++;
+			});
+	}
+
+	if (Requests.empty())
+	{
+		return CbPackage{};
+	}
+
+	CbPackage	   RpcResponse;
+	CbObjectWriter ResponseObject;
+	ResponseObject.BeginArray("Result"sv);
+	for (const RequestData& Request : Requests)
+	{
+		ResponseObject.BeginObject();
+		{
+			const CompressedBuffer& Result = Request.Result;
+			if (Result)
+			{
+				ResponseObject.AddHash("RawHash"sv, Request.RawHash);
+				if (!EnumHasAllFlags(Request.Policy, CachePolicy::SkipData))
+				{
+					RpcResponse.AddAttachment(CbAttachment(Result, Request.RawHash));
+				}
+				else
+				{
+					ResponseObject.AddInteger("RawSize"sv, Request.RawSize);
+				}
+			}
+			else if (Request.RawHash != IoHash::Zero)
+			{
+				ResponseObject.AddHash("RawHash"sv, Request.RawHash);
+				ResponseObject.AddInteger("RawSize"sv, Request.RawSize);
+			}
+		}
+		ResponseObject.EndObject();
+	}
+	ResponseObject.EndArray();
+
+	RpcResponse.SetObject(ResponseObject.Save());
+	return RpcResponse;
+}
+
+namespace cache::detail {
+
+	struct RecordValue
+	{
+		Oid		 ValueId;
+		IoHash	 ContentId;
+		uint64_t RawSize;
+	};
+	struct RecordBody
+	{
+		IoBuffer					CacheValue;
+		std::vector<RecordValue>	Values;
+		const UpstreamEndpointInfo* Source = nullptr;
+		CachePolicy					DownstreamPolicy;
+		bool						Exists	   = false;
+		bool						HasRequest = false;
+		bool						ValuesRead = false;
+	};
+	struct ChunkRequest
+	{
+		CacheChunkRequest*			Key	   = nullptr;
+		RecordBody*					Record = nullptr;
+		CompressedBuffer			Value;
+		const UpstreamEndpointInfo* Source			= nullptr;
+		uint64_t					RawSize			= 0;
+		uint64_t					RequestedSize	= 0;
+		uint64_t					RequestedOffset = 0;
+		CachePolicy					DownstreamPolicy;
+		bool						Exists			= false;
+		bool						RawSizeKnown	= false;
+		bool						IsRecordRequest = false;
+		uint64_t					ElapsedTimeUs	= 0;
+	};
+
+}  // namespace cache::detail
+
+CbPackage
+HttpStructuredCacheService::HandleRpcGetCacheChunks(CbObjectView RpcRequest)
+{
+	using namespace cache::detail;
+
+	std::string						Namespace;
+	std::vector<CacheKeyRequest>	RecordKeys;		 // Data about a Record necessary to identify it to the upstream
+	std::vector<RecordBody>			Records;		 // Scratch-space data about a Record when fulfilling RecordRequests
+	std::vector<CacheChunkRequest>	RequestKeys;	 // Data about a ChunkRequest necessary to identify it to the upstream
+	std::vector<ChunkRequest>		Requests;		 // Intermediate and result data about a ChunkRequest
+	std::vector<ChunkRequest*>		RecordRequests;	 // The ChunkRequests that are requesting a subvalue from a Record Key
+	std::vector<ChunkRequest*>		ValueRequests;	 // The ChunkRequests that are requesting a Value Key
+	std::vector<CacheChunkRequest*> UpstreamChunks;	 // ChunkRequests that we need to send to the upstream
+
+	// Parse requests from the CompactBinary body of the RpcRequest and divide it into RecordRequests and ValueRequests
+	if (!ParseGetCacheChunksRequest(Namespace, RecordKeys, Records, RequestKeys, Requests, RecordRequests, ValueRequests, RpcRequest))
+	{
+		return CbPackage{};
+	}
+
+	// For each Record request, load the Record if necessary to find the Chunk's ContentId, load its Payloads if we
+	// have it locally, and otherwise append a request for the payload to UpstreamChunks
+	GetLocalCacheRecords(Namespace, RecordKeys, Records, RecordRequests, UpstreamChunks);
+
+	// For each Value request, load the Value if we have it locally and otherwise append a request for the payload to UpstreamChunks
+	GetLocalCacheValues(Namespace, ValueRequests, UpstreamChunks);
+
+	// Call GetCacheChunks on the upstream for any payloads we do not have locally
+	GetUpstreamCacheChunks(Namespace, UpstreamChunks, RequestKeys, Requests);
+
+	// Send the payload and descriptive data about each chunk to the client
+	return WriteGetCacheChunksResponse(Namespace, Requests);
+}
+
+bool
+HttpStructuredCacheService::ParseGetCacheChunksRequest(std::string&								  Namespace,
+													   std::vector<CacheKeyRequest>&			  RecordKeys,
+													   std::vector<cache::detail::RecordBody>&	  Records,
+													   std::vector<CacheChunkRequest>&			  RequestKeys,
+													   std::vector<cache::detail::ChunkRequest>&  Requests,
+													   std::vector<cache::detail::ChunkRequest*>& RecordRequests,
+													   std::vector<cache::detail::ChunkRequest*>& ValueRequests,
+													   CbObjectView								  RpcRequest)
+{
+	using namespace cache::detail;
+
+	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheChunks"sv);
+
+	CbObjectView	 Params			   = RpcRequest["Params"sv].AsObjectView();
+	std::string_view DefaultPolicyText = Params["DefaultPolicy"sv].AsString();
+	CachePolicy		 DefaultPolicy	   = !DefaultPolicyText.empty() ? ParseCachePolicy(DefaultPolicyText) : CachePolicy::Default;
+
+	std::optional<std::string> NamespaceText = GetRpcRequestNamespace(Params);
+	if (!NamespaceText)
+	{
+		ZEN_WARN("GetCacheChunks: Invalid namespace in ChunkRequest.");
+		return false;
+	}
+	Namespace = *NamespaceText;
+
+	CbArrayView ChunkRequestsArray = Params["ChunkRequests"sv].AsArrayView();
+	size_t		NumRequests		   = static_cast<size_t>(ChunkRequestsArray.Num());
+
+	// Note that these reservations allow us to take pointers to the elements while populating them. If the reservation is removed,
+	// we will need to change the pointers to indexes to handle reallocations.
+	RecordKeys.reserve(NumRequests);
+	Records.reserve(NumRequests);
+	RequestKeys.reserve(NumRequests);
+	Requests.reserve(NumRequests);
+	RecordRequests.reserve(NumRequests);
+	ValueRequests.reserve(NumRequests);
+
+	CacheKeyRequest* PreviousRecordKey = nullptr;
+	RecordBody*		 PreviousRecord	   = nullptr;
+
+	for (CbFieldView RequestView : ChunkRequestsArray)
+	{
+		CbObjectView	   RequestObject = RequestView.AsObjectView();
+		CacheChunkRequest& RequestKey	 = RequestKeys.emplace_back();
+		ChunkRequest&	   Request		 = Requests.emplace_back();
+		CbObjectView	   KeyObject	 = RequestObject["Key"sv].AsObjectView();
+
+		Request.Key = &RequestKey;
+		if (!GetRpcRequestCacheKey(KeyObject, Request.Key->Key))
+		{
+			ZEN_WARN("GetCacheChunks: Invalid key in ChunkRequest.");
+			return false;
+		}
+
+		RequestKey.ChunkId			= RequestObject["ChunkId"sv].AsHash();
+		RequestKey.ValueId			= RequestObject["ValueId"sv].AsObjectId();
+		RequestKey.RawOffset		= RequestObject["RawOffset"sv].AsUInt64();
+		RequestKey.RawSize			= RequestObject["RawSize"sv].AsUInt64(UINT64_MAX);
+		Request.RequestedSize		= RequestKey.RawSize;
+		Request.RequestedOffset		= RequestKey.RawOffset;
+		std::string_view PolicyText = RequestObject["Policy"sv].AsString();
+		Request.DownstreamPolicy	= !PolicyText.empty() ? ParseCachePolicy(PolicyText) : DefaultPolicy;
+		Request.IsRecordRequest		= (bool)RequestKey.ValueId;
+
+		if (!Request.IsRecordRequest)
+		{
+			ValueRequests.push_back(&Request);
+		}
+		else
+		{
+			RecordRequests.push_back(&Request);
+			CacheKeyRequest* RecordKey = nullptr;
+			RecordBody*		 Record	   = nullptr;
+
+			if (!PreviousRecordKey || PreviousRecordKey->Key < RequestKey.Key)
+			{
+				RecordKey		  = &RecordKeys.emplace_back();
+				PreviousRecordKey = RecordKey;
+				Record			  = &Records.emplace_back();
+				PreviousRecord	  = Record;
+				RecordKey->Key	  = RequestKey.Key;
+			}
+			else if (RequestKey.Key == PreviousRecordKey->Key)
+			{
+				RecordKey = PreviousRecordKey;
+				Record	  = PreviousRecord;
+			}
+			else
+			{
+				ZEN_WARN("GetCacheChunks: Keys in ChunkRequest are not sorted: {}/{} came after {}/{}.",
+						 RequestKey.Key.Bucket,
+						 RequestKey.Key.Hash,
+						 PreviousRecordKey->Key.Bucket,
+						 PreviousRecordKey->Key.Hash);
+				return false;
+			}
+			Request.Record = Record;
+			if (RequestKey.ChunkId == RequestKey.ChunkId.Zero)
+			{
+				Record->DownstreamPolicy =
+					Record->HasRequest ? Union(Record->DownstreamPolicy, Request.DownstreamPolicy) : Request.DownstreamPolicy;
+				Record->HasRequest = true;
+			}
+		}
+	}
+	if (Requests.empty())
+	{
+		return false;
+	}
+	return true;
+}
+
+void
+HttpStructuredCacheService::GetLocalCacheRecords(std::string_view							Namespace,
+												 std::vector<CacheKeyRequest>&				RecordKeys,
+												 std::vector<cache::detail::RecordBody>&	Records,
+												 std::vector<cache::detail::ChunkRequest*>& RecordRequests,
+												 std::vector<CacheChunkRequest*>&			OutUpstreamChunks)
+{
+	using namespace cache::detail;
+
+	std::vector<CacheKeyRequest*> UpstreamRecordRequests;
+	for (size_t RecordIndex = 0; RecordIndex < Records.size(); ++RecordIndex)
+	{
+		Stopwatch		 Timer;
+		CacheKeyRequest& RecordKey = RecordKeys[RecordIndex];
+		RecordBody&		 Record	   = Records[RecordIndex];
+		if (Record.HasRequest)
+		{
+			Record.DownstreamPolicy |= CachePolicy::SkipData | CachePolicy::SkipMeta;
+
+			if (!Record.Exists && EnumHasAllFlags(Record.DownstreamPolicy, CachePolicy::QueryLocal))
+			{
+				ZenCacheValue CacheValue;
+				if (m_CacheStore.Get(Namespace, RecordKey.Key.Bucket, RecordKey.Key.Hash, CacheValue))
+				{
+					Record.Exists	  = true;
+					Record.CacheValue = std::move(CacheValue.Value);
+				}
+			}
+			if (!Record.Exists && EnumHasAllFlags(Record.DownstreamPolicy, CachePolicy::QueryRemote))
+			{
+				RecordKey.Policy = CacheRecordPolicy(ConvertToUpstream(Record.DownstreamPolicy));
+				UpstreamRecordRequests.push_back(&RecordKey);
+			}
+			RecordRequests[RecordIndex]->ElapsedTimeUs += Timer.GetElapsedTimeUs();
+		}
+	}
+
+	if (!UpstreamRecordRequests.empty())
+	{
+		const auto OnCacheRecordGetComplete =
+			[this, Namespace, &RecordKeys, &Records, &RecordRequests](CacheRecordGetCompleteParams&& Params) {
+				if (!Params.Record)
+				{
+					return;
+				}
+				CacheKeyRequest& RecordKey	 = Params.Request;
+				size_t			 RecordIndex = std::distance(RecordKeys.data(), &RecordKey);
+				RecordRequests[RecordIndex]->ElapsedTimeUs += static_cast<uint64_t>(Params.ElapsedSeconds * 1000000.0);
+				RecordBody& Record = Records[RecordIndex];
+
+				const CacheKey& Key	  = RecordKey.Key;
+				Record.Exists		  = true;
+				CbObject ObjectBuffer = CbObject::Clone(Params.Record);
+				Record.CacheValue	  = ObjectBuffer.GetBuffer().AsIoBuffer();
+				Record.CacheValue.SetContentType(ZenContentType::kCbObject);
+				Record.Source = Params.Source;
+
+				if (EnumHasAllFlags(Record.DownstreamPolicy, CachePolicy::StoreLocal))
+				{
+					m_CacheStore.Put(Namespace, Key.Bucket, Key.Hash, {.Value = Record.CacheValue});
+				}
+			};
+		m_UpstreamCache.GetCacheRecords(Namespace, UpstreamRecordRequests, std::move(OnCacheRecordGetComplete));
+	}
+
+	std::vector<CacheChunkRequest*> UpstreamPayloadRequests;
+	for (ChunkRequest* Request : RecordRequests)
+	{
+		Stopwatch Timer;
+		if (Request->Key->ChunkId == IoHash::Zero)
+		{
+			// Unreal uses a 12 byte ID to address cache record values. When the uncompressed hash (ChunkId)
+			// is missing, parse the cache record and try to find the raw hash from the ValueId.
+			RecordBody& Record = *Request->Record;
+			if (!Record.ValuesRead)
+			{
+				Record.ValuesRead = true;
+				if (Record.CacheValue && Record.CacheValue.GetContentType() == ZenContentType::kCbObject)
+				{
+					CbObjectView RecordObject = CbObjectView(Record.CacheValue.GetData());
+					CbArrayView	 ValuesArray  = RecordObject["Values"sv].AsArrayView();
+					Record.Values.reserve(ValuesArray.Num());
+					for (CbFieldView ValueField : ValuesArray)
+					{
+						CbObjectView ValueObject  = ValueField.AsObjectView();
+						Oid			 ValueId	  = ValueObject["Id"sv].AsObjectId();
+						CbFieldView	 RawHashField = ValueObject["RawHash"sv];
+						IoHash		 RawHash	  = RawHashField.AsBinaryAttachment();
+						if (ValueId && !RawHashField.HasError())
+						{
+							Record.Values.push_back({ValueId, RawHash, ValueObject["RawSize"sv].AsUInt64()});
+						}
+					}
+				}
+			}
+
+			for (const RecordValue& Value : Record.Values)
+			{
+				if (Value.ValueId == Request->Key->ValueId)
+				{
+					Request->Key->ChunkId = Value.ContentId;
+					Request->RawSize	  = Value.RawSize;
+					Request->RawSizeKnown = true;
+					break;
+				}
+			}
+		}
+
+		// Now load the ContentId from the local ContentIdStore or from the upstream
+		if (Request->Key->ChunkId != IoHash::Zero)
+		{
+			if (EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::QueryLocal))
+			{
+				if (EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::SkipData) && Request->RawSizeKnown)
+				{
+					if (m_CidStore.ContainsChunk(Request->Key->ChunkId))
+					{
+						Request->Exists = true;
+					}
+				}
+				else if (IoBuffer Payload = m_CidStore.FindChunkByCid(Request->Key->ChunkId))
+				{
+					if (!EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::SkipData))
+					{
+						Request->Value = CompressedBuffer::FromCompressedNoValidate(std::move(Payload));
+						if (Request->Value)
+						{
+							Request->Exists		  = true;
+							Request->RawSizeKnown = false;
+						}
+					}
+					else
+					{
+						IoHash _;
+						if (CompressedBuffer::ValidateCompressedHeader(Payload, _, Request->RawSize))
+						{
+							Request->Exists		  = true;
+							Request->RawSizeKnown = true;
+						}
+					}
+				}
+			}
+			if (!Request->Exists && EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::QueryRemote))
+			{
+				Request->Key->Policy = ConvertToUpstream(Request->DownstreamPolicy);
+				OutUpstreamChunks.push_back(Request->Key);
+			}
+		}
+		Request->ElapsedTimeUs += Timer.GetElapsedTimeUs();
+	}
+}
+
+void
+HttpStructuredCacheService::GetLocalCacheValues(std::string_view						   Namespace,
+												std::vector<cache::detail::ChunkRequest*>& ValueRequests,
+												std::vector<CacheChunkRequest*>&		   OutUpstreamChunks)
+{
+	using namespace cache::detail;
+
+	for (ChunkRequest* Request : ValueRequests)
+	{
+		Stopwatch Timer;
+		if (!Request->Exists && EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::QueryLocal))
+		{
+			ZenCacheValue CacheValue;
+			if (m_CacheStore.Get(Namespace, Request->Key->Key.Bucket, Request->Key->Key.Hash, CacheValue))
+			{
+				if (IsCompressedBinary(CacheValue.Value.GetContentType()))
+				{
+					Request->Key->ChunkId = CacheValue.RawHash;
+					Request->Exists		  = true;
+					Request->RawSize	  = CacheValue.RawSize;
+					Request->RawSizeKnown = true;
+					if (!EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::SkipData))
+					{
+						Request->Value = CompressedBuffer::FromCompressedNoValidate(std::move(CacheValue.Value));
+					}
+				}
+			}
+		}
+		if (!Request->Exists && EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::QueryRemote))
+		{
+			if (EnumHasAllFlags(Request->DownstreamPolicy, CachePolicy::StoreLocal))
+			{
+				// Convert the Offset,Size request into a request for the entire value; we will need it all to be able to store it locally
+				Request->Key->RawOffset = 0;
+				Request->Key->RawSize	= UINT64_MAX;
+			}
+			OutUpstreamChunks.push_back(Request->Key);
+		}
+		Request->ElapsedTimeUs += Timer.GetElapsedTimeUs();
+	}
+}
+
+void
+HttpStructuredCacheService::GetUpstreamCacheChunks(std::string_view							 Namespace,
+												   std::vector<CacheChunkRequest*>&			 UpstreamChunks,
+												   std::vector<CacheChunkRequest>&			 RequestKeys,
+												   std::vector<cache::detail::ChunkRequest>& Requests)
+{
+	using namespace cache::detail;
+
+	if (!UpstreamChunks.empty())
+	{
+		const auto OnCacheChunksGetComplete = [this, Namespace, &RequestKeys, &Requests](CacheChunkGetCompleteParams&& Params) {
+			if (Params.RawHash == Params.RawHash.Zero)
+			{
+				return;
+			}
+
+			CacheChunkRequest& Key			= Params.Request;
+			size_t			   RequestIndex = std::distance(RequestKeys.data(), &Key);
+			ChunkRequest&	   Request		= Requests[RequestIndex];
+			Request.ElapsedTimeUs += static_cast<uint64_t>(Params.ElapsedSeconds * 1000000.0);
+			if (EnumHasAllFlags(Request.DownstreamPolicy, CachePolicy::StoreLocal) ||
+				!EnumHasAllFlags(Request.DownstreamPolicy, CachePolicy::SkipData))
+			{
+				CompressedBuffer Compressed = CompressedBuffer::FromCompressedNoValidate(IoBuffer(Params.Value));
+				if (!Compressed)
+				{
+					return;
+				}
+
+				if (EnumHasAllFlags(Request.DownstreamPolicy, CachePolicy::StoreLocal))
+				{
+					if (Request.IsRecordRequest)
+					{
+						m_CidStore.AddChunk(Params.Value, Params.RawHash);
+					}
+					else
+					{
+						m_CacheStore.Put(Namespace,
+										 Key.Key.Bucket,
+										 Key.Key.Hash,
+										 {.Value = Params.Value, .RawSize = Params.RawSize, .RawHash = Params.RawHash});
+					}
+				}
+				if (!EnumHasAllFlags(Request.DownstreamPolicy, CachePolicy::SkipData))
+				{
+					Request.Value = std::move(Compressed);
+				}
+			}
+			Key.ChunkId			 = Params.RawHash;
+			Request.Exists		 = true;
+			Request.RawSize		 = Params.RawSize;
+			Request.RawSizeKnown = true;
+			Request.Source		 = Params.Source;
+
+			m_CacheStats.UpstreamHitCount++;
+		};
+
+		m_UpstreamCache.GetCacheChunks(Namespace, UpstreamChunks, std::move(OnCacheChunksGetComplete));
+	}
+}
+
+CbPackage
+HttpStructuredCacheService::WriteGetCacheChunksResponse(std::string_view Namespace, std::vector<cache::detail::ChunkRequest>& Requests)
+{
+	using namespace cache::detail;
+
+	CbPackage	   RpcResponse;
+	CbObjectWriter Writer;
+
+	Writer.BeginArray("Result"sv);
+	for (ChunkRequest& Request : Requests)
+	{
+		Writer.BeginObject();
+		{
+			if (Request.Exists)
+			{
+				Writer.AddHash("RawHash"sv, Request.Key->ChunkId);
+				if (Request.Value && !EnumHasAllFlags(Request.DownstreamPolicy, CachePolicy::SkipData))
+				{
+					RpcResponse.AddAttachment(CbAttachment(Request.Value, Request.Key->ChunkId));
+				}
+				else
+				{
+					Writer.AddInteger("RawSize"sv, Request.RawSize);
+				}
+
+				ZEN_DEBUG("GETCACHECHUNKS HIT - '{}/{}/{}/{}' {} '{}' ({}) in {}",
+						  Namespace,
+						  Request.Key->Key.Bucket,
+						  Request.Key->Key.Hash,
+						  Request.Key->ValueId,
+						  NiceBytes(Request.RawSize),
+						  Request.IsRecordRequest ? "Record"sv : "Value"sv,
+						  Request.Source ? Request.Source->Url : "LOCAL"sv,
+						  NiceLatencyNs(Request.ElapsedTimeUs * 1000));
+				m_CacheStats.HitCount++;
+			}
+			else if (!EnumHasAnyFlags(Request.DownstreamPolicy, CachePolicy::Query))
+			{
+				ZEN_DEBUG("GETCACHECHUNKS DISABLEDQUERY - '{}/{}/{}/{}' in {}",
+						  Namespace,
+						  Request.Key->Key.Bucket,
+						  Request.Key->Key.Hash,
+						  Request.Key->ValueId,
+						  NiceLatencyNs(Request.ElapsedTimeUs * 1000));
+			}
+			else
+			{
+				ZEN_DEBUG("GETCACHECHUNKS MISS - '{}/{}/{}/{}' in {}",
+						  Namespace,
+						  Request.Key->Key.Bucket,
+						  Request.Key->Key.Hash,
+						  Request.Key->ValueId,
+						  NiceLatencyNs(Request.ElapsedTimeUs * 1000));
+				m_CacheStats.MissCount++;
+			}
+		}
+		Writer.EndObject();
+	}
+	Writer.EndArray();
+
+	RpcResponse.SetObject(Writer.Save());
+	return RpcResponse;
+}
+
+void
+HttpStructuredCacheService::HandleStatsRequest(HttpServerRequest& Request)
+{
+	CbObjectWriter Cbo;
+
+	EmitSnapshot("requests", m_HttpRequests, Cbo);
+	EmitSnapshot("upstream_gets", m_UpstreamGetRequestTiming, Cbo);
+
+	const uint64_t HitCount			= m_CacheStats.HitCount;
+	const uint64_t UpstreamHitCount = m_CacheStats.UpstreamHitCount;
+	const uint64_t MissCount		= m_CacheStats.MissCount;
+	const uint64_t TotalCount		= HitCount + MissCount;
+
+	const CidStoreSize	CidSize	  = m_CidStore.TotalSize();
+	const GcStorageSize CacheSize = m_CacheStore.StorageSize();
+
+	Cbo.BeginObject("cache");
+	{
+		Cbo.BeginObject("size");
+		{
+			Cbo << "disk" << CacheSize.DiskSize;
+			Cbo << "memory" << CacheSize.MemorySize;
+		}
+		Cbo.EndObject();
+
+		Cbo << "upstream_ratio" << (HitCount > 0 ? (double(UpstreamHitCount) / double(HitCount)) : 0.0);
+		Cbo << "hits" << HitCount << "misses" << MissCount;
+		Cbo << "hit_ratio" << (TotalCount > 0 ? (double(HitCount) / double(TotalCount)) : 0.0);
+		Cbo << "upstream_hits" << m_CacheStats.UpstreamHitCount;
+		Cbo << "upstream_ratio" << (HitCount > 0 ? (double(UpstreamHitCount) / double(HitCount)) : 0.0);
+	}
+	Cbo.EndObject();
+
+	Cbo.BeginObject("upstream");
+	{
+		m_UpstreamCache.GetStatus(Cbo);
+	}
+	Cbo.EndObject();
+
+	Cbo.BeginObject("cid");
+	{
+		Cbo.BeginObject("size");
+		{
+			Cbo << "tiny" << CidSize.TinySize;
+			Cbo << "small" << CidSize.SmallSize;
+			Cbo << "large" << CidSize.LargeSize;
+			Cbo << "total" << CidSize.TotalSize;
+		}
+		Cbo.EndObject();
+	}
+	Cbo.EndObject();
+
+	Request.WriteResponse(HttpResponseCode::OK, Cbo.Save());
+}
+
+void
+HttpStructuredCacheService::HandleStatusRequest(HttpServerRequest& Request)
+{
+	CbObjectWriter Cbo;
+	Cbo << "ok" << true;
+	Request.WriteResponse(HttpResponseCode::OK, Cbo.Save());
+}
+
+#if ZEN_WITH_TESTS
+
+TEST_CASE("z$service.parse.relative.Uri")
+{
+	HttpRequestData RootRequest;
+	CHECK(HttpRequestParseRelativeUri("", RootRequest));
+	CHECK(!RootRequest.Namespace.has_value());
+	CHECK(!RootRequest.Bucket.has_value());
+	CHECK(!RootRequest.HashKey.has_value());
+	CHECK(!RootRequest.ValueContentId.has_value());
+
+	RootRequest = {};
+	CHECK(HttpRequestParseRelativeUri("/", RootRequest));
+	CHECK(!RootRequest.Namespace.has_value());
+	CHECK(!RootRequest.Bucket.has_value());
+	CHECK(!RootRequest.HashKey.has_value());
+	CHECK(!RootRequest.ValueContentId.has_value());
+
+	HttpRequestData LegacyBucketRequestBecomesNamespaceRequest;
+	CHECK(HttpRequestParseRelativeUri("test", LegacyBucketRequestBecomesNamespaceRequest));
+	CHECK(LegacyBucketRequestBecomesNamespaceRequest.Namespace == "test"sv);
+	CHECK(!LegacyBucketRequestBecomesNamespaceRequest.Bucket.has_value());
+	CHECK(!LegacyBucketRequestBecomesNamespaceRequest.HashKey.has_value());
+	CHECK(!LegacyBucketRequestBecomesNamespaceRequest.ValueContentId.has_value());
+
+	HttpRequestData LegacyHashKeyRequest;
+	CHECK(HttpRequestParseRelativeUri("test/0123456789abcdef12340123456789abcdef1234", LegacyHashKeyRequest));
+	CHECK(LegacyHashKeyRequest.Namespace == ZenCacheStore::DefaultNamespace);
+	CHECK(LegacyHashKeyRequest.Bucket == "test"sv);
+	CHECK(LegacyHashKeyRequest.HashKey == IoHash::FromHexString("0123456789abcdef12340123456789abcdef1234"sv));
+	CHECK(!LegacyHashKeyRequest.ValueContentId.has_value());
+
+	HttpRequestData LegacyValueContentIdRequest;
+	CHECK(HttpRequestParseRelativeUri("test/0123456789abcdef12340123456789abcdef1234/56789abcdef12345678956789abcdef123456789",
+									  LegacyValueContentIdRequest));
+	CHECK(LegacyValueContentIdRequest.Namespace == ZenCacheStore::DefaultNamespace);
+	CHECK(LegacyValueContentIdRequest.Bucket == "test"sv);
+	CHECK(LegacyValueContentIdRequest.HashKey == IoHash::FromHexString("0123456789abcdef12340123456789abcdef1234"sv));
+	CHECK(LegacyValueContentIdRequest.ValueContentId == IoHash::FromHexString("56789abcdef12345678956789abcdef123456789"sv));
+
+	HttpRequestData V2DefaultNamespaceRequest;
+	CHECK(HttpRequestParseRelativeUri("ue4.ddc", V2DefaultNamespaceRequest));
+	CHECK(V2DefaultNamespaceRequest.Namespace == "ue4.ddc");
+	CHECK(!V2DefaultNamespaceRequest.Bucket.has_value());
+	CHECK(!V2DefaultNamespaceRequest.HashKey.has_value());
+	CHECK(!V2DefaultNamespaceRequest.ValueContentId.has_value());
+
+	HttpRequestData V2NamespaceRequest;
+	CHECK(HttpRequestParseRelativeUri("nicenamespace", V2NamespaceRequest));
+	CHECK(V2NamespaceRequest.Namespace == "nicenamespace"sv);
+	CHECK(!V2NamespaceRequest.Bucket.has_value());
+	CHECK(!V2NamespaceRequest.HashKey.has_value());
+	CHECK(!V2NamespaceRequest.ValueContentId.has_value());
+
+	HttpRequestData V2BucketRequestWithDefaultNamespace;
+	CHECK(HttpRequestParseRelativeUri("ue4.ddc/test", V2BucketRequestWithDefaultNamespace));
+	CHECK(V2BucketRequestWithDefaultNamespace.Namespace == "ue4.ddc");
+	CHECK(V2BucketRequestWithDefaultNamespace.Bucket == "test"sv);
+	CHECK(!V2BucketRequestWithDefaultNamespace.HashKey.has_value());
+	CHECK(!V2BucketRequestWithDefaultNamespace.ValueContentId.has_value());
+
+	HttpRequestData V2BucketRequestWithNamespace;
+	CHECK(HttpRequestParseRelativeUri("nicenamespace/test", V2BucketRequestWithNamespace));
+	CHECK(V2BucketRequestWithNamespace.Namespace == "nicenamespace"sv);
+	CHECK(V2BucketRequestWithNamespace.Bucket == "test"sv);
+	CHECK(!V2BucketRequestWithNamespace.HashKey.has_value());
+	CHECK(!V2BucketRequestWithNamespace.ValueContentId.has_value());
+
+	HttpRequestData V2HashKeyRequest;
+	CHECK(HttpRequestParseRelativeUri("test/0123456789abcdef12340123456789abcdef1234", V2HashKeyRequest));
+	CHECK(V2HashKeyRequest.Namespace == ZenCacheStore::DefaultNamespace);
+	CHECK(V2HashKeyRequest.Bucket == "test");
+	CHECK(V2HashKeyRequest.HashKey == IoHash::FromHexString("0123456789abcdef12340123456789abcdef1234"sv));
+	CHECK(!V2HashKeyRequest.ValueContentId.has_value());
+
+	HttpRequestData V2ValueContentIdRequest;
+	CHECK(
+		HttpRequestParseRelativeUri("nicenamespace/test/0123456789abcdef12340123456789abcdef1234/56789abcdef12345678956789abcdef123456789",
+									V2ValueContentIdRequest));
+	CHECK(V2ValueContentIdRequest.Namespace == "nicenamespace"sv);
+	CHECK(V2ValueContentIdRequest.Bucket == "test"sv);
+	CHECK(V2ValueContentIdRequest.HashKey == IoHash::FromHexString("0123456789abcdef12340123456789abcdef1234"sv));
+	CHECK(V2ValueContentIdRequest.ValueContentId == IoHash::FromHexString("56789abcdef12345678956789abcdef123456789"sv));
+
+	HttpRequestData Invalid;
+	CHECK(!HttpRequestParseRelativeUri("bad\2_namespace", Invalid));
+	CHECK(!HttpRequestParseRelativeUri("nice/\2\1bucket", Invalid));
+	CHECK(!HttpRequestParseRelativeUri("namespace/bucket/0123456789a", Invalid));
+	CHECK(!HttpRequestParseRelativeUri("namespace/bucket/0123456789abcdef12340123456789abcdef1234/56789abcdef1234", Invalid));
+	CHECK(!HttpRequestParseRelativeUri("namespace/bucket/pppppppp89abcdef12340123456789abcdef1234", Invalid));
+	CHECK(!HttpRequestParseRelativeUri("namespace/bucket/0123456789abcdef12340123456789abcdef1234/56789abcd", Invalid));
+	CHECK(!HttpRequestParseRelativeUri("namespace/bucket/0123456789abcdef12340123456789abcdef1234/ppppppppdef12345678956789abcdef123456789",
+									   Invalid));
+}
+
+#endif
+
+void
+z$service_forcelink()
+{
+}
+
+}  // namespace zen
diff --git a/src/zenserver/cache/structuredcache.h b/src/zenserver/cache/structuredcache.h
new file mode 100644
index 000000000..4e7b98ac9
--- /dev/null
+++ b/src/zenserver/cache/structuredcache.h
@@ -0,0 +1,187 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include <zencore/stats.h>
+#include <zenhttp/httpserver.h>
+
+#include "monitoring/httpstats.h"
+#include "monitoring/httpstatus.h"
+
+#include <memory>
+#include <vector>
+
+namespace spdlog {
+class logger;
+}
+
+namespace zen {
+
+struct CacheChunkRequest;
+struct CacheKeyRequest;
+class CidStore;
+class CbObjectView;
+struct PutRequestData;
+class ScrubContext;
+class UpstreamCache;
+class ZenCacheStore;
+enum class CachePolicy : uint32_t;
+enum class RpcAcceptOptions : uint16_t;
+
+namespace cache {
+	class IRpcRequestReplayer;
+	class IRpcRequestRecorder;
+	namespace detail {
+		struct RecordBody;
+		struct ChunkRequest;
+	}  // namespace detail
+}  // namespace cache
+
+/**
+ * Structured cache service. Imposes constraints on keys, supports blobs and
+ * structured values
+ *
+ * Keys are structured as:
+ *
+ *   {BucketId}/{KeyHash}
+ *
+ * Where BucketId is a lower-case alphanumeric string, and KeyHash is a 40-character
+ * hexadecimal sequence. The hash value may be derived in any number of ways, it's
+ * up to the application to pick an approach.
+ *
+ * Values may be structured or unstructured. Structured values are encoded using Unreal
+ * Engine's compact binary encoding (see CbObject)
+ *
+ * Additionally, attachments may be addressed as:
+ *
+ *   {BucketId}/{KeyHash}/{ValueHash}
+ *
+ * Where the two initial components are the same as for the main endpoint
+ *
+ * The storage strategy is as follows:
+ *
+ *  - Structured values are stored in a dedicated backing store per bucket
+ *  - Unstructured values and attachments are stored in the CAS pool
+ *
+ */
+
+class HttpStructuredCacheService : public HttpService, public IHttpStatsProvider, public IHttpStatusProvider
+{
+public:
+	HttpStructuredCacheService(ZenCacheStore&	  InCacheStore,
+							   CidStore&		  InCidStore,
+							   HttpStatsService&  StatsService,
+							   HttpStatusService& StatusService,
+							   UpstreamCache&	  UpstreamCache);
+	~HttpStructuredCacheService();
+
+	virtual const char* BaseUri() const override;
+	virtual void		HandleRequest(HttpServerRequest& Request) override;
+
+	void Flush();
+	void Scrub(ScrubContext& Ctx);
+
+private:
+	struct CacheRef
+	{
+		std::string Namespace;
+		std::string BucketSegment;
+		IoHash		HashKey;
+		IoHash		ValueContentId;
+	};
+
+	struct CacheStats
+	{
+		std::atomic_uint64_t HitCount{};
+		std::atomic_uint64_t UpstreamHitCount{};
+		std::atomic_uint64_t MissCount{};
+	};
+	enum class PutResult
+	{
+		Success,
+		Fail,
+		Invalid,
+	};
+
+	void HandleCacheRecordRequest(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl);
+	void HandleGetCacheRecord(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl);
+	void HandlePutCacheRecord(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl);
+	void HandleCacheChunkRequest(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl);
+	void HandleGetCacheChunk(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl);
+	void HandlePutCacheChunk(HttpServerRequest& Request, const CacheRef& Ref, CachePolicy PolicyFromUrl);
+	void HandleRpcRequest(HttpServerRequest& Request);
+	void HandleDetailsRequest(HttpServerRequest& Request);
+
+	CbPackage HandleRpcPutCacheRecords(const CbPackage& BatchRequest);
+	CbPackage HandleRpcGetCacheRecords(CbObjectView BatchRequest);
+	CbPackage HandleRpcPutCacheValues(const CbPackage& BatchRequest);
+	CbPackage HandleRpcGetCacheValues(CbObjectView BatchRequest);
+	CbPackage HandleRpcGetCacheChunks(CbObjectView BatchRequest);
+	CbPackage HandleRpcRequest(const ZenContentType ContentType,
+							   IoBuffer&&			Body,
+							   uint32_t&			OutAcceptMagic,
+							   RpcAcceptOptions&	OutAcceptFlags,
+							   int&					OutTargetProcessId);
+
+	void		 HandleCacheRequest(HttpServerRequest& Request);
+	void		 HandleCacheNamespaceRequest(HttpServerRequest& Request, std::string_view Namespace);
+	void		 HandleCacheBucketRequest(HttpServerRequest& Request, std::string_view Namespace, std::string_view Bucket);
+	virtual void HandleStatsRequest(HttpServerRequest& Request) override;
+	virtual void HandleStatusRequest(HttpServerRequest& Request) override;
+	PutResult	 PutCacheRecord(PutRequestData& Request, const CbPackage* Package);
+
+	/** HandleRpcGetCacheChunks Helper: Parse the Body object into RecordValue Requests and Value Requests. */
+	bool ParseGetCacheChunksRequest(std::string&							   Namespace,
+									std::vector<CacheKeyRequest>&			   RecordKeys,
+									std::vector<cache::detail::RecordBody>&	   Records,
+									std::vector<CacheChunkRequest>&			   RequestKeys,
+									std::vector<cache::detail::ChunkRequest>&  Requests,
+									std::vector<cache::detail::ChunkRequest*>& RecordRequests,
+									std::vector<cache::detail::ChunkRequest*>& ValueRequests,
+									CbObjectView							   RpcRequest);
+	/** HandleRpcGetCacheChunks Helper: Load records to get ContentId for RecordRequests, and load their payloads if they exist locally. */
+	void GetLocalCacheRecords(std::string_view							 Namespace,
+							  std::vector<CacheKeyRequest>&				 RecordKeys,
+							  std::vector<cache::detail::RecordBody>&	 Records,
+							  std::vector<cache::detail::ChunkRequest*>& RecordRequests,
+							  std::vector<CacheChunkRequest*>&			 OutUpstreamChunks);
+	/** HandleRpcGetCacheChunks Helper: For ValueRequests, load their payloads if they exist locally. */
+	void GetLocalCacheValues(std::string_view							Namespace,
+							 std::vector<cache::detail::ChunkRequest*>& ValueRequests,
+							 std::vector<CacheChunkRequest*>&			OutUpstreamChunks);
+	/** HandleRpcGetCacheChunks Helper: Load payloads from upstream that did not exist locally. */
+	void GetUpstreamCacheChunks(std::string_view						  Namespace,
+								std::vector<CacheChunkRequest*>&		  UpstreamChunks,
+								std::vector<CacheChunkRequest>&			  RequestKeys,
+								std::vector<cache::detail::ChunkRequest>& Requests);
+	/** HandleRpcGetCacheChunks Helper: Send response message containing all chunk results. */
+	CbPackage WriteGetCacheChunksResponse(std::string_view Namespace, std::vector<cache::detail::ChunkRequest>& Requests);
+
+	spdlog::logger&			 Log() { return m_Log; }
+	spdlog::logger&			 m_Log;
+	ZenCacheStore&			 m_CacheStore;
+	HttpStatsService&		 m_StatsService;
+	HttpStatusService&		 m_StatusService;
+	CidStore&				 m_CidStore;
+	UpstreamCache&			 m_UpstreamCache;
+	uint64_t				 m_LastScrubTime = 0;
+	metrics::OperationTiming m_HttpRequests;
+	metrics::OperationTiming m_UpstreamGetRequestTiming;
+	CacheStats				 m_CacheStats;
+
+	void ReplayRequestRecorder(cache::IRpcRequestReplayer& Replayer, uint32_t ThreadCount);
+
+	std::unique_ptr<cache::IRpcRequestRecorder> m_RequestRecorder;
+};
+
+/** Recognize both kBinary and kCompressedBinary as kCompressedBinary for structured cache value keys.
+ * We need this until the content type is preserved for kCompressedBinary when passing to and from upstream servers. */
+inline bool
+IsCompressedBinary(ZenContentType Type)
+{
+	return Type == ZenContentType::kBinary || Type == ZenContentType::kCompressedBinary;
+}
+
+void z$service_forcelink();
+
+}  // namespace zen
diff --git a/src/zenserver/cache/structuredcachestore.cpp b/src/zenserver/cache/structuredcachestore.cpp
new file mode 100644
index 000000000..26e970073
--- /dev/null
+++ b/src/zenserver/cache/structuredcachestore.cpp
@@ -0,0 +1,3648 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include "structuredcachestore.h"
+
+#include <zencore/except.h>
+
+#include <zencore/compactbinarybuilder.h>
+#include <zencore/compactbinarypackage.h>
+#include <zencore/compactbinaryvalidation.h>
+#include <zencore/compress.h>
+#include <zencore/except.h>
+#include <zencore/filesystem.h>
+#include <zencore/fmtutils.h>
+#include <zencore/logging.h>
+#include <zencore/scopeguard.h>
+#include <zencore/string.h>
+#include <zencore/thread.h>
+#include <zencore/timer.h>
+#include <zencore/trace.h>
+#include <zenstore/cidstore.h>
+#include <zenstore/scrubcontext.h>
+
+#include <xxhash.h>
+
+#include <limits>
+
+#if ZEN_PLATFORM_WINDOWS
+#	include <zencore/windows.h>
+#endif
+
+ZEN_THIRD_PARTY_INCLUDES_START
+#include <fmt/core.h>
+#include <gsl/gsl-lite.hpp>
+ZEN_THIRD_PARTY_INCLUDES_END
+
+#if ZEN_WITH_TESTS
+#	include <zencore/testing.h>
+#	include <zencore/testutils.h>
+#	include <zencore/workthreadpool.h>
+#	include <random>
+#endif
+
+//////////////////////////////////////////////////////////////////////////
+
+namespace zen {
+
+namespace {
+
+#pragma pack(push)
+#pragma pack(1)
+
+	struct CacheBucketIndexHeader
+	{
+		static constexpr uint32_t ExpectedMagic	 = 0x75696478;	// 'uidx';
+		static constexpr uint32_t Version2		 = 2;
+		static constexpr uint32_t CurrentVersion = Version2;
+
+		uint32_t Magic			  = ExpectedMagic;
+		uint32_t Version		  = CurrentVersion;
+		uint64_t EntryCount		  = 0;
+		uint64_t LogPosition	  = 0;
+		uint32_t PayloadAlignment = 0;
+		uint32_t Checksum		  = 0;
+
+		static uint32_t ComputeChecksum(const CacheBucketIndexHeader& Header)
+		{
+			return XXH32(&Header.Magic, sizeof(CacheBucketIndexHeader) - sizeof(uint32_t), 0xC0C0'BABA);
+		}
+	};
+
+	static_assert(sizeof(CacheBucketIndexHeader) == 32);
+
+#pragma pack(pop)
+
+	const char* IndexExtension = ".uidx";
+	const char* LogExtension   = ".slog";
+
+	std::filesystem::path GetIndexPath(const std::filesystem::path& BucketDir, const std::string& BucketName)
+	{
+		return BucketDir / (BucketName + IndexExtension);
+	}
+
+	std::filesystem::path GetTempIndexPath(const std::filesystem::path& BucketDir, const std::string& BucketName)
+	{
+		return BucketDir / (BucketName + ".tmp");
+	}
+
+	std::filesystem::path GetLogPath(const std::filesystem::path& BucketDir, const std::string& BucketName)
+	{
+		return BucketDir / (BucketName + LogExtension);
+	}
+
+	bool ValidateEntry(const DiskIndexEntry& Entry, std::string& OutReason)
+	{
+		if (Entry.Key == IoHash::Zero)
+		{
+			OutReason = fmt::format("Invalid hash key {}", Entry.Key.ToHexString());
+			return false;
+		}
+		if (Entry.Location.GetFlags() &
+			~(DiskLocation::kStandaloneFile | DiskLocation::kStructured | DiskLocation::kTombStone | DiskLocation::kCompressed))
+		{
+			OutReason = fmt::format("Invalid flags {} for entry {}", Entry.Location.GetFlags(), Entry.Key.ToHexString());
+			return false;
+		}
+		if (Entry.Location.IsFlagSet(DiskLocation::kTombStone))
+		{
+			return true;
+		}
+		if (Entry.Location.Reserved != 0)
+		{
+			OutReason = fmt::format("Invalid reserved field {} for entry {}", Entry.Location.Reserved, Entry.Key.ToHexString());
+			return false;
+		}
+		uint64_t Size = Entry.Location.Size();
+		if (Size == 0)
+		{
+			OutReason = fmt::format("Invalid size {} for entry {}", Size, Entry.Key.ToHexString());
+			return false;
+		}
+		return true;
+	}
+
+	bool MoveAndDeleteDirectory(const std::filesystem::path& Dir)
+	{
+		int DropIndex = 0;
+		do
+		{
+			if (!std::filesystem::exists(Dir))
+			{
+				return false;
+			}
+
+			std::string			  DroppedName		= fmt::format("[dropped]{}({})", Dir.filename().string(), DropIndex);
+			std::filesystem::path DroppedBucketPath = Dir.parent_path() / DroppedName;
+			if (std::filesystem::exists(DroppedBucketPath))
+			{
+				DropIndex++;
+				continue;
+			}
+
+			std::error_code Ec;
+			std::filesystem::rename(Dir, DroppedBucketPath, Ec);
+			if (!Ec)
+			{
+				DeleteDirectories(DroppedBucketPath);
+				return true;
+			}
+			// TODO: Do we need to bail at some point?
+			zen::Sleep(100);
+		} while (true);
+	}
+
+}  // namespace
+
+namespace fs = std::filesystem;
+
+static CbObject
+LoadCompactBinaryObject(const fs::path& Path)
+{
+	FileContents Result = ReadFile(Path);
+
+	if (!Result.ErrorCode)
+	{
+		IoBuffer Buffer = Result.Flatten();
+		if (CbValidateError Error = ValidateCompactBinary(Buffer, CbValidateMode::All); Error == CbValidateError::None)
+		{
+			return LoadCompactBinaryObject(Buffer);
+		}
+	}
+
+	return CbObject();
+}
+
+static void
+SaveCompactBinaryObject(const fs::path& Path, const CbObject& Object)
+{
+	WriteFile(Path, Object.GetBuffer().AsIoBuffer());
+}
+
+ZenCacheNamespace::ZenCacheNamespace(GcManager& Gc, const std::filesystem::path& RootDir)
+: GcStorage(Gc)
+, GcContributor(Gc)
+, m_RootDir(RootDir)
+, m_DiskLayer(RootDir)
+{
+	ZEN_INFO("initializing structured cache at '{}'", RootDir);
+	CreateDirectories(RootDir);
+
+	m_DiskLayer.DiscoverBuckets();
+
+#if ZEN_USE_CACHE_TRACKER
+	m_AccessTracker.reset(new ZenCacheTracker(RootDir));
+#endif
+}
+
+ZenCacheNamespace::~ZenCacheNamespace()
+{
+}
+
+bool
+ZenCacheNamespace::Get(std::string_view InBucket, const IoHash& HashKey, ZenCacheValue& OutValue)
+{
+	ZEN_TRACE_CPU("Z$::Get");
+
+	bool Ok = m_MemLayer.Get(InBucket, HashKey, OutValue);
+
+#if ZEN_USE_CACHE_TRACKER
+	auto _ = MakeGuard([&] {
+		if (!Ok)
+			return;
+
+		m_AccessTracker->TrackAccess(InBucket, HashKey);
+	});
+#endif
+
+	if (Ok)
+	{
+		ZEN_ASSERT(OutValue.Value.Size());
+
+		return true;
+	}
+
+	Ok = m_DiskLayer.Get(InBucket, HashKey, OutValue);
+
+	if (Ok)
+	{
+		ZEN_ASSERT(OutValue.Value.Size());
+
+		if (OutValue.Value.Size() <= m_DiskLayerSizeThreshold)
+		{
+			m_MemLayer.Put(InBucket, HashKey, OutValue);
+		}
+	}
+
+	return Ok;
+}
+
+void
+ZenCacheNamespace::Put(std::string_view InBucket, const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	ZEN_TRACE_CPU("Z$::Put");
+
+	// Store value and index
+
+	ZEN_ASSERT(Value.Value.Size());
+
+	m_DiskLayer.Put(InBucket, HashKey, Value);
+
+#if ZEN_USE_REF_TRACKING
+	if (Value.Value.GetContentType() == ZenContentType::kCbObject)
+	{
+		if (ValidateCompactBinary(Value.Value, CbValidateMode::All) == CbValidateError::None)
+		{
+			CbObject Object{SharedBuffer(Value.Value)};
+
+			uint8_t								TempBuffer[8 * sizeof(IoHash)];
+			std::pmr::monotonic_buffer_resource Linear{TempBuffer, sizeof TempBuffer};
+			std::pmr::polymorphic_allocator		Allocator{&Linear};
+			std::pmr::vector<IoHash>			CidReferences{Allocator};
+
+			Object.IterateAttachments([&](CbFieldView Field) { CidReferences.push_back(Field.AsAttachment()); });
+
+			m_Gc.OnNewCidReferences(CidReferences);
+		}
+	}
+#endif
+
+	if (Value.Value.Size() <= m_DiskLayerSizeThreshold)
+	{
+		m_MemLayer.Put(InBucket, HashKey, Value);
+	}
+}
+
+bool
+ZenCacheNamespace::DropBucket(std::string_view Bucket)
+{
+	ZEN_INFO("dropping bucket '{}'", Bucket);
+
+	// TODO: should ensure this is done atomically across all layers
+
+	const bool MemDropped  = m_MemLayer.DropBucket(Bucket);
+	const bool DiskDropped = m_DiskLayer.DropBucket(Bucket);
+	const bool AnyDropped  = MemDropped || DiskDropped;
+
+	ZEN_INFO("bucket '{}' was {}", Bucket, AnyDropped ? "dropped" : "not found");
+
+	return AnyDropped;
+}
+
+bool
+ZenCacheNamespace::Drop()
+{
+	m_MemLayer.Drop();
+	return m_DiskLayer.Drop();
+}
+
+void
+ZenCacheNamespace::Flush()
+{
+	m_DiskLayer.Flush();
+}
+
+void
+ZenCacheNamespace::Scrub(ScrubContext& Ctx)
+{
+	if (m_LastScrubTime == Ctx.ScrubTimestamp())
+	{
+		return;
+	}
+
+	m_LastScrubTime = Ctx.ScrubTimestamp();
+
+	m_DiskLayer.Scrub(Ctx);
+	m_MemLayer.Scrub(Ctx);
+}
+
+void
+ZenCacheNamespace::GatherReferences(GcContext& GcCtx)
+{
+	Stopwatch  Timer;
+	const auto Guard =
+		MakeGuard([&] { ZEN_DEBUG("cache gathered all references from '{}' in {}", m_RootDir, NiceTimeSpanMs(Timer.GetElapsedTimeMs())); });
+
+	access_tracking::AccessTimes AccessTimes;
+	m_MemLayer.GatherAccessTimes(AccessTimes);
+
+	m_DiskLayer.UpdateAccessTimes(AccessTimes);
+	m_DiskLayer.GatherReferences(GcCtx);
+}
+
+void
+ZenCacheNamespace::CollectGarbage(GcContext& GcCtx)
+{
+	m_MemLayer.Reset();
+	m_DiskLayer.CollectGarbage(GcCtx);
+}
+
+GcStorageSize
+ZenCacheNamespace::StorageSize() const
+{
+	return {.DiskSize = m_DiskLayer.TotalSize(), .MemorySize = m_MemLayer.TotalSize()};
+}
+
+ZenCacheNamespace::Info
+ZenCacheNamespace::GetInfo() const
+{
+	ZenCacheNamespace::Info			Info = {.Config			 = {.RootDir = m_RootDir, .DiskLayerThreshold = m_DiskLayerSizeThreshold},
+											.DiskLayerInfo	 = m_DiskLayer.GetInfo(),
+											.MemoryLayerInfo = m_MemLayer.GetInfo()};
+	std::unordered_set<std::string> BucketNames;
+	for (const std::string& BucketName : Info.DiskLayerInfo.BucketNames)
+	{
+		BucketNames.insert(BucketName);
+	}
+	for (const std::string& BucketName : Info.MemoryLayerInfo.BucketNames)
+	{
+		BucketNames.insert(BucketName);
+	}
+	Info.BucketNames.insert(Info.BucketNames.end(), BucketNames.begin(), BucketNames.end());
+	return Info;
+}
+
+std::optional<ZenCacheNamespace::BucketInfo>
+ZenCacheNamespace::GetBucketInfo(std::string_view Bucket) const
+{
+	std::optional<ZenCacheDiskLayer::BucketInfo> DiskBucketInfo = m_DiskLayer.GetBucketInfo(Bucket);
+	if (!DiskBucketInfo.has_value())
+	{
+		return {};
+	}
+	ZenCacheNamespace::BucketInfo Info = {.DiskLayerInfo   = *DiskBucketInfo,
+										  .MemoryLayerInfo = m_MemLayer.GetBucketInfo(Bucket).value_or(ZenCacheMemoryLayer::BucketInfo{})};
+	return Info;
+}
+
+CacheValueDetails::NamespaceDetails
+ZenCacheNamespace::GetValueDetails(const std::string_view BucketFilter, const std::string_view ValueFilter) const
+{
+	return m_DiskLayer.GetValueDetails(BucketFilter, ValueFilter);
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+ZenCacheMemoryLayer::ZenCacheMemoryLayer()
+{
+}
+
+ZenCacheMemoryLayer::~ZenCacheMemoryLayer()
+{
+}
+
+bool
+ZenCacheMemoryLayer::Get(std::string_view InBucket, const IoHash& HashKey, ZenCacheValue& OutValue)
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	auto It = m_Buckets.find(std::string(InBucket));
+
+	if (It == m_Buckets.end())
+	{
+		return false;
+	}
+
+	CacheBucket* Bucket = It->second.get();
+
+	_.ReleaseNow();
+
+	// There's a race here. Since the lock is released early to allow
+	// inserts, the bucket delete path could end up deleting the
+	// underlying data structure
+
+	return Bucket->Get(HashKey, OutValue);
+}
+
+void
+ZenCacheMemoryLayer::Put(std::string_view InBucket, const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	const auto	 BucketName = std::string(InBucket);
+	CacheBucket* Bucket		= nullptr;
+
+	{
+		RwLock::SharedLockScope _(m_Lock);
+
+		if (auto It = m_Buckets.find(std::string(InBucket)); It != m_Buckets.end())
+		{
+			Bucket = It->second.get();
+		}
+	}
+
+	if (Bucket == nullptr)
+	{
+		// New bucket
+
+		RwLock::ExclusiveLockScope _(m_Lock);
+
+		if (auto It = m_Buckets.find(std::string(InBucket)); It != m_Buckets.end())
+		{
+			Bucket = It->second.get();
+		}
+		else
+		{
+			auto InsertResult = m_Buckets.emplace(BucketName, std::make_unique<CacheBucket>());
+			Bucket			  = InsertResult.first->second.get();
+		}
+	}
+
+	// Note that since the underlying IoBuffer is retained, the content type is also
+
+	Bucket->Put(HashKey, Value);
+}
+
+bool
+ZenCacheMemoryLayer::DropBucket(std::string_view InBucket)
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+
+	auto It = m_Buckets.find(std::string(InBucket));
+
+	if (It != m_Buckets.end())
+	{
+		CacheBucket& Bucket = *It->second;
+		m_DroppedBuckets.push_back(std::move(It->second));
+		m_Buckets.erase(It);
+		Bucket.Drop();
+		return true;
+	}
+	return false;
+}
+
+void
+ZenCacheMemoryLayer::Drop()
+{
+	RwLock::ExclusiveLockScope				  _(m_Lock);
+	std::vector<std::unique_ptr<CacheBucket>> Buckets;
+	Buckets.reserve(m_Buckets.size());
+	while (!m_Buckets.empty())
+	{
+		const auto&	 It		= m_Buckets.begin();
+		CacheBucket& Bucket = *It->second;
+		m_DroppedBuckets.push_back(std::move(It->second));
+		m_Buckets.erase(It->first);
+		Bucket.Drop();
+	}
+}
+
+void
+ZenCacheMemoryLayer::Scrub(ScrubContext& Ctx)
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		Kv.second->Scrub(Ctx);
+	}
+}
+
+void
+ZenCacheMemoryLayer::GatherAccessTimes(zen::access_tracking::AccessTimes& AccessTimes)
+{
+	using namespace zen::access_tracking;
+
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		std::vector<KeyAccessTime>& Bucket = AccessTimes.Buckets[Kv.first];
+		Kv.second->GatherAccessTimes(Bucket);
+	}
+}
+
+void
+ZenCacheMemoryLayer::Reset()
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+	m_Buckets.clear();
+}
+
+uint64_t
+ZenCacheMemoryLayer::TotalSize() const
+{
+	uint64_t				TotalSize{};
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		TotalSize += Kv.second->TotalSize();
+	}
+
+	return TotalSize;
+}
+
+ZenCacheMemoryLayer::Info
+ZenCacheMemoryLayer::GetInfo() const
+{
+	ZenCacheMemoryLayer::Info Info = {.Config = m_Configuration, .TotalSize = TotalSize()};
+
+	RwLock::SharedLockScope _(m_Lock);
+	Info.BucketNames.reserve(m_Buckets.size());
+	for (auto& Kv : m_Buckets)
+	{
+		Info.BucketNames.push_back(Kv.first);
+		Info.EntryCount += Kv.second->EntryCount();
+	}
+	return Info;
+}
+
+std::optional<ZenCacheMemoryLayer::BucketInfo>
+ZenCacheMemoryLayer::GetBucketInfo(std::string_view Bucket) const
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	if (auto It = m_Buckets.find(std::string(Bucket)); It != m_Buckets.end())
+	{
+		return ZenCacheMemoryLayer::BucketInfo{.EntryCount = It->second->EntryCount(), .TotalSize = It->second->TotalSize()};
+	}
+	return {};
+}
+
+void
+ZenCacheMemoryLayer::CacheBucket::Scrub(ScrubContext& Ctx)
+{
+	RwLock::SharedLockScope _(m_BucketLock);
+
+	std::vector<IoHash> BadHashes;
+
+	auto ValidateEntry = [](const IoHash& Hash, ZenContentType ContentType, IoBuffer Buffer) {
+		if (ContentType == ZenContentType::kCbObject)
+		{
+			CbValidateError Error = ValidateCompactBinary(Buffer, CbValidateMode::All);
+			return Error == CbValidateError::None;
+		}
+		if (ContentType == ZenContentType::kCompressedBinary)
+		{
+			IoHash	 RawHash;
+			uint64_t RawSize;
+			if (!CompressedBuffer::ValidateCompressedHeader(Buffer, RawHash, RawSize))
+			{
+				return false;
+			}
+			if (Hash != RawHash)
+			{
+				return false;
+			}
+		}
+		return true;
+	};
+
+	for (auto& Kv : m_CacheMap)
+	{
+		const BucketPayload& Payload = m_Payloads[Kv.second];
+		if (!ValidateEntry(Kv.first, Payload.Payload.GetContentType(), Payload.Payload))
+		{
+			BadHashes.push_back(Kv.first);
+		}
+	}
+
+	if (!BadHashes.empty())
+	{
+		Ctx.ReportBadCidChunks(BadHashes);
+	}
+}
+
+void
+ZenCacheMemoryLayer::CacheBucket::GatherAccessTimes(std::vector<zen::access_tracking::KeyAccessTime>& AccessTimes)
+{
+	RwLock::SharedLockScope _(m_BucketLock);
+	std::transform(m_CacheMap.begin(), m_CacheMap.end(), std::back_inserter(AccessTimes), [this](const auto& Kv) {
+		return access_tracking::KeyAccessTime{.Key = Kv.first, .LastAccess = m_AccessTimes[Kv.second]};
+	});
+}
+
+bool
+ZenCacheMemoryLayer::CacheBucket::Get(const IoHash& HashKey, ZenCacheValue& OutValue)
+{
+	RwLock::SharedLockScope _(m_BucketLock);
+
+	if (auto It = m_CacheMap.find(HashKey); It != m_CacheMap.end())
+	{
+		uint32_t EntryIndex = It.value();
+		ZEN_ASSERT_SLOW(EntryIndex < m_Payloads.size());
+		ZEN_ASSERT_SLOW(m_AccessTimes.size() == m_Payloads.size());
+
+		const BucketPayload& Payload = m_Payloads[EntryIndex];
+		OutValue					 = {.Value = Payload.Payload, .RawSize = Payload.RawSize, .RawHash = Payload.RawHash};
+		m_AccessTimes[EntryIndex]	 = GcClock::TickCount();
+
+		return true;
+	}
+
+	return false;
+}
+
+void
+ZenCacheMemoryLayer::CacheBucket::Put(const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	size_t PayloadSize = Value.Value.GetSize();
+	{
+		GcClock::Tick			   AccessTime = GcClock::TickCount();
+		RwLock::ExclusiveLockScope _(m_BucketLock);
+		if (m_CacheMap.size() == std::numeric_limits<uint32_t>::max())
+		{
+			// No more space in our memory cache!
+			return;
+		}
+		if (auto It = m_CacheMap.find(HashKey); It != m_CacheMap.end())
+		{
+			uint32_t EntryIndex = It.value();
+			ZEN_ASSERT_SLOW(EntryIndex < m_Payloads.size());
+
+			m_TotalSize.fetch_sub(PayloadSize, std::memory_order::relaxed);
+			BucketPayload& Payload	  = m_Payloads[EntryIndex];
+			Payload.Payload			  = Value.Value;
+			Payload.RawHash			  = Value.RawHash;
+			Payload.RawSize			  = gsl::narrow<uint32_t>(Value.RawSize);
+			m_AccessTimes[EntryIndex] = AccessTime;
+		}
+		else
+		{
+			uint32_t EntryIndex = gsl::narrow<uint32_t>(m_Payloads.size());
+			m_Payloads.emplace_back(
+				BucketPayload{.Payload = Value.Value, .RawSize = gsl::narrow<uint32_t>(Value.RawSize), .RawHash = Value.RawHash});
+			m_AccessTimes.emplace_back(AccessTime);
+			m_CacheMap.insert_or_assign(HashKey, EntryIndex);
+		}
+		ZEN_ASSERT_SLOW(m_Payloads.size() == m_CacheMap.size());
+		ZEN_ASSERT_SLOW(m_AccessTimes.size() == m_Payloads.size());
+	}
+
+	m_TotalSize.fetch_add(PayloadSize, std::memory_order::relaxed);
+}
+
+void
+ZenCacheMemoryLayer::CacheBucket::Drop()
+{
+	RwLock::ExclusiveLockScope _(m_BucketLock);
+	m_CacheMap.clear();
+	m_AccessTimes.clear();
+	m_Payloads.clear();
+	m_TotalSize.store(0);
+}
+
+uint64_t
+ZenCacheMemoryLayer::CacheBucket::EntryCount() const
+{
+	RwLock::SharedLockScope _(m_BucketLock);
+	return static_cast<uint64_t>(m_CacheMap.size());
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+ZenCacheDiskLayer::CacheBucket::CacheBucket(std::string BucketName) : m_BucketName(std::move(BucketName)), m_BucketId(Oid::Zero)
+{
+}
+
+ZenCacheDiskLayer::CacheBucket::~CacheBucket()
+{
+}
+
+bool
+ZenCacheDiskLayer::CacheBucket::OpenOrCreate(std::filesystem::path BucketDir, bool AllowCreate)
+{
+	using namespace std::literals;
+
+	m_BlocksBasePath = BucketDir / "blocks";
+	m_BucketDir		 = BucketDir;
+
+	CreateDirectories(m_BucketDir);
+
+	std::filesystem::path ManifestPath{m_BucketDir / "zen_manifest"};
+
+	bool IsNew = false;
+
+	CbObject Manifest = LoadCompactBinaryObject(ManifestPath);
+
+	if (Manifest)
+	{
+		m_BucketId = Manifest["BucketId"sv].AsObjectId();
+		if (m_BucketId == Oid::Zero)
+		{
+			return false;
+		}
+	}
+	else if (AllowCreate)
+	{
+		m_BucketId.Generate();
+
+		CbObjectWriter Writer;
+		Writer << "BucketId"sv << m_BucketId;
+		Manifest = Writer.Save();
+		SaveCompactBinaryObject(ManifestPath, Manifest);
+		IsNew = true;
+	}
+	else
+	{
+		return false;
+	}
+
+	OpenLog(IsNew);
+
+	if (!IsNew)
+	{
+		Stopwatch  Timer;
+		const auto _ =
+			MakeGuard([&] { ZEN_INFO("read store manifest '{}' in {}", ManifestPath, NiceTimeSpanMs(Timer.GetElapsedTimeMs())); });
+
+		for (CbFieldView Entry : Manifest["Timestamps"sv])
+		{
+			const CbObjectView Obj = Entry.AsObjectView();
+			const IoHash	   Key = Obj["Key"sv].AsHash();
+
+			if (auto It = m_Index.find(Key); It != m_Index.end())
+			{
+				size_t EntryIndex = It.value();
+				ZEN_ASSERT_SLOW(EntryIndex < m_AccessTimes.size());
+				m_AccessTimes[EntryIndex] = Obj["LastAccess"sv].AsInt64();
+			}
+		}
+		for (CbFieldView Entry : Manifest["RawInfo"sv])
+		{
+			const CbObjectView Obj = Entry.AsObjectView();
+			const IoHash	   Key = Obj["Key"sv].AsHash();
+			if (auto It = m_Index.find(Key); It != m_Index.end())
+			{
+				size_t EntryIndex = It.value();
+				ZEN_ASSERT_SLOW(EntryIndex < m_Payloads.size());
+				m_Payloads[EntryIndex].RawHash = Obj["RawHash"sv].AsHash();
+				m_Payloads[EntryIndex].RawSize = Obj["RawSize"sv].AsUInt64();
+			}
+		}
+	}
+
+	return true;
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::MakeIndexSnapshot()
+{
+	uint64_t LogCount = m_SlogFile.GetLogCount();
+	if (m_LogFlushPosition == LogCount)
+	{
+		return;
+	}
+
+	ZEN_DEBUG("write store snapshot for '{}'", m_BucketDir / m_BucketName);
+	uint64_t   EntryCount = 0;
+	Stopwatch  Timer;
+	const auto _ = MakeGuard([&] {
+		ZEN_INFO("wrote store snapshot for '{}' containing {} entries in {}",
+				 m_BucketDir / m_BucketName,
+				 EntryCount,
+				 NiceTimeSpanMs(Timer.GetElapsedTimeMs()));
+	});
+
+	namespace fs = std::filesystem;
+
+	fs::path IndexPath	   = GetIndexPath(m_BucketDir, m_BucketName);
+	fs::path STmpIndexPath = GetTempIndexPath(m_BucketDir, m_BucketName);
+
+	// Move index away, we keep it if something goes wrong
+	if (fs::is_regular_file(STmpIndexPath))
+	{
+		fs::remove(STmpIndexPath);
+	}
+	if (fs::is_regular_file(IndexPath))
+	{
+		fs::rename(IndexPath, STmpIndexPath);
+	}
+
+	try
+	{
+		// Write the current state of the location map to a new index state
+		std::vector<DiskIndexEntry> Entries;
+
+		{
+			Entries.resize(m_Index.size());
+
+			uint64_t EntryIndex = 0;
+			for (auto& Entry : m_Index)
+			{
+				DiskIndexEntry& IndexEntry = Entries[EntryIndex++];
+				IndexEntry.Key			   = Entry.first;
+				IndexEntry.Location		   = m_Payloads[Entry.second].Location;
+			}
+		}
+
+		BasicFile ObjectIndexFile;
+		ObjectIndexFile.Open(IndexPath, BasicFile::Mode::kTruncate);
+		CacheBucketIndexHeader Header = {.EntryCount	   = Entries.size(),
+										 .LogPosition	   = LogCount,
+										 .PayloadAlignment = gsl::narrow<uint32_t>(m_PayloadAlignment)};
+
+		Header.Checksum = CacheBucketIndexHeader::ComputeChecksum(Header);
+
+		ObjectIndexFile.Write(&Header, sizeof(CacheBucketIndexHeader), 0);
+		ObjectIndexFile.Write(Entries.data(), Entries.size() * sizeof(DiskIndexEntry), sizeof(CacheBucketIndexHeader));
+		ObjectIndexFile.Flush();
+		ObjectIndexFile.Close();
+		EntryCount		   = Entries.size();
+		m_LogFlushPosition = LogCount;
+	}
+	catch (std::exception& Err)
+	{
+		ZEN_ERROR("snapshot FAILED, reason: '{}'", Err.what());
+
+		// Restore any previous snapshot
+
+		if (fs::is_regular_file(STmpIndexPath))
+		{
+			fs::remove(IndexPath);
+			fs::rename(STmpIndexPath, IndexPath);
+		}
+	}
+	if (fs::is_regular_file(STmpIndexPath))
+	{
+		fs::remove(STmpIndexPath);
+	}
+}
+
+uint64_t
+ZenCacheDiskLayer::CacheBucket::ReadIndexFile(const std::filesystem::path& IndexPath, uint32_t& OutVersion)
+{
+	if (std::filesystem::is_regular_file(IndexPath))
+	{
+		BasicFile ObjectIndexFile;
+		ObjectIndexFile.Open(IndexPath, BasicFile::Mode::kRead);
+		uint64_t Size = ObjectIndexFile.FileSize();
+		if (Size >= sizeof(CacheBucketIndexHeader))
+		{
+			CacheBucketIndexHeader Header;
+			ObjectIndexFile.Read(&Header, sizeof(Header), 0);
+			if ((Header.Magic == CacheBucketIndexHeader::ExpectedMagic) &&
+				(Header.Checksum == CacheBucketIndexHeader::ComputeChecksum(Header)) && (Header.PayloadAlignment > 0))
+			{
+				switch (Header.Version)
+				{
+					case CacheBucketIndexHeader::Version2:
+						{
+							uint64_t ExpectedEntryCount = (Size - sizeof(sizeof(CacheBucketIndexHeader))) / sizeof(DiskIndexEntry);
+							if (Header.EntryCount > ExpectedEntryCount)
+							{
+								break;
+							}
+							size_t	   EntryCount = 0;
+							Stopwatch  Timer;
+							const auto _ = MakeGuard([&] {
+								ZEN_INFO("read store '{}' index containing {} entries in {}",
+										 IndexPath,
+										 EntryCount,
+										 NiceTimeSpanMs(Timer.GetElapsedTimeMs()));
+							});
+
+							m_PayloadAlignment = Header.PayloadAlignment;
+
+							std::vector<DiskIndexEntry> Entries;
+							Entries.resize(Header.EntryCount);
+							ObjectIndexFile.Read(Entries.data(),
+												 Header.EntryCount * sizeof(DiskIndexEntry),
+												 sizeof(CacheBucketIndexHeader));
+
+							m_Payloads.reserve(Header.EntryCount);
+							m_AccessTimes.reserve(Header.EntryCount);
+							m_Index.reserve(Header.EntryCount);
+
+							std::string InvalidEntryReason;
+							for (const DiskIndexEntry& Entry : Entries)
+							{
+								if (!ValidateEntry(Entry, InvalidEntryReason))
+								{
+									ZEN_WARN("skipping invalid entry in '{}', reason: '{}'", IndexPath, InvalidEntryReason);
+									continue;
+								}
+								size_t EntryIndex = m_Payloads.size();
+								m_Payloads.emplace_back(BucketPayload{.Location = Entry.Location, .RawSize = 0, .RawHash = IoHash::Zero});
+								m_AccessTimes.emplace_back(GcClock::TickCount());
+								m_Index.insert_or_assign(Entry.Key, EntryIndex);
+								EntryCount++;
+							}
+							OutVersion = CacheBucketIndexHeader::Version2;
+							return Header.LogPosition;
+						}
+						break;
+					default:
+						break;
+				}
+			}
+		}
+		ZEN_WARN("skipping invalid index file '{}'", IndexPath);
+	}
+	return 0;
+}
+
+uint64_t
+ZenCacheDiskLayer::CacheBucket::ReadLog(const std::filesystem::path& LogPath, uint64_t SkipEntryCount)
+{
+	if (std::filesystem::is_regular_file(LogPath))
+	{
+		uint64_t					LogEntryCount = 0;
+		Stopwatch					Timer;
+		const auto					_ = MakeGuard([&] {
+			 ZEN_INFO("read store '{}' log containing {} entries in {}", LogPath, LogEntryCount, NiceTimeSpanMs(Timer.GetElapsedTimeMs()));
+		 });
+		TCasLogFile<DiskIndexEntry> CasLog;
+		CasLog.Open(LogPath, CasLogFile::Mode::kRead);
+		if (CasLog.Initialize())
+		{
+			uint64_t EntryCount = CasLog.GetLogCount();
+			if (EntryCount < SkipEntryCount)
+			{
+				ZEN_WARN("reading full log at '{}', reason: Log position from index snapshot is out of range", LogPath);
+				SkipEntryCount = 0;
+			}
+			LogEntryCount = EntryCount - SkipEntryCount;
+			m_Index.reserve(LogEntryCount);
+			uint64_t InvalidEntryCount = 0;
+			CasLog.Replay(
+				[&](const DiskIndexEntry& Record) {
+					std::string InvalidEntryReason;
+					if (Record.Location.Flags & DiskLocation::kTombStone)
+					{
+						m_Index.erase(Record.Key);
+						return;
+					}
+					if (!ValidateEntry(Record, InvalidEntryReason))
+					{
+						ZEN_WARN("skipping invalid entry in '{}', reason: '{}'", LogPath, InvalidEntryReason);
+						++InvalidEntryCount;
+						return;
+					}
+					size_t EntryIndex = m_Payloads.size();
+					m_Payloads.emplace_back(BucketPayload{.Location = Record.Location, .RawSize = 0u, .RawHash = IoHash::Zero});
+					m_AccessTimes.emplace_back(GcClock::TickCount());
+					m_Index.insert_or_assign(Record.Key, EntryIndex);
+				},
+				SkipEntryCount);
+			if (InvalidEntryCount)
+			{
+				ZEN_WARN("found {} invalid entries in '{}'", InvalidEntryCount, m_BucketDir / m_BucketName);
+			}
+			return LogEntryCount;
+		}
+	}
+	return 0;
+};
+
+void
+ZenCacheDiskLayer::CacheBucket::OpenLog(const bool IsNew)
+{
+	m_TotalStandaloneSize = 0;
+
+	m_Index.clear();
+	m_Payloads.clear();
+	m_AccessTimes.clear();
+
+	std::filesystem::path LogPath	= GetLogPath(m_BucketDir, m_BucketName);
+	std::filesystem::path IndexPath = GetIndexPath(m_BucketDir, m_BucketName);
+
+	if (IsNew)
+	{
+		fs::remove(LogPath);
+		fs::remove(IndexPath);
+		fs::remove_all(m_BlocksBasePath);
+	}
+
+	uint64_t LogEntryCount = 0;
+	{
+		uint32_t IndexVersion = 0;
+		m_LogFlushPosition	  = ReadIndexFile(IndexPath, IndexVersion);
+		if (IndexVersion == 0 && std::filesystem::is_regular_file(IndexPath))
+		{
+			ZEN_WARN("removing invalid index file at '{}'", IndexPath);
+			fs::remove(IndexPath);
+		}
+
+		if (TCasLogFile<DiskIndexEntry>::IsValid(LogPath))
+		{
+			LogEntryCount = ReadLog(LogPath, m_LogFlushPosition);
+		}
+		else
+		{
+			ZEN_WARN("removing invalid cas log at '{}'", LogPath);
+			fs::remove(LogPath);
+		}
+	}
+
+	CreateDirectories(m_BucketDir);
+
+	m_SlogFile.Open(LogPath, CasLogFile::Mode::kWrite);
+
+	std::vector<BlockStoreLocation> KnownLocations;
+	KnownLocations.reserve(m_Index.size());
+	for (const auto& Entry : m_Index)
+	{
+		size_t				 EntryIndex = Entry.second;
+		const BucketPayload& Payload	= m_Payloads[EntryIndex];
+		const DiskLocation&	 Location	= Payload.Location;
+
+		if (Location.IsFlagSet(DiskLocation::kStandaloneFile))
+		{
+			m_TotalStandaloneSize.fetch_add(Location.Size(), std::memory_order::relaxed);
+			continue;
+		}
+		const BlockStoreLocation& BlockLocation = Location.GetBlockLocation(m_PayloadAlignment);
+		KnownLocations.push_back(BlockLocation);
+	}
+
+	m_BlockStore.Initialize(m_BlocksBasePath, MaxBlockSize, BlockStoreDiskLocation::MaxBlockIndex + 1, KnownLocations);
+	if (IsNew || LogEntryCount > 0)
+	{
+		MakeIndexSnapshot();
+	}
+	// TODO: should validate integrity of container files here
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::BuildPath(PathBuilderBase& Path, const IoHash& HashKey) const
+{
+	char HexString[sizeof(HashKey.Hash) * 2];
+	ToHexBytes(HashKey.Hash, sizeof HashKey.Hash, HexString);
+
+	Path.Append(m_BucketDir);
+	Path.AppendSeparator();
+	Path.Append(L"blob");
+	Path.AppendSeparator();
+	Path.AppendAsciiRange(HexString, HexString + 3);
+	Path.AppendSeparator();
+	Path.AppendAsciiRange(HexString + 3, HexString + 5);
+	Path.AppendSeparator();
+	Path.AppendAsciiRange(HexString + 5, HexString + sizeof(HexString));
+}
+
+IoBuffer
+ZenCacheDiskLayer::CacheBucket::GetInlineCacheValue(const DiskLocation& Loc) const
+{
+	BlockStoreLocation Location = Loc.GetBlockLocation(m_PayloadAlignment);
+
+	IoBuffer Value = m_BlockStore.TryGetChunk(Location);
+	if (Value)
+	{
+		Value.SetContentType(Loc.GetContentType());
+	}
+
+	return Value;
+}
+
+IoBuffer
+ZenCacheDiskLayer::CacheBucket::GetStandaloneCacheValue(const DiskLocation& Loc, const IoHash& HashKey) const
+{
+	ExtendablePathBuilder<256> DataFilePath;
+	BuildPath(DataFilePath, HashKey);
+
+	RwLock::SharedLockScope ValueLock(LockForHash(HashKey));
+
+	if (IoBuffer Data = IoBufferBuilder::MakeFromFile(DataFilePath.ToPath()))
+	{
+		Data.SetContentType(Loc.GetContentType());
+
+		return Data;
+	}
+
+	return {};
+}
+
+bool
+ZenCacheDiskLayer::CacheBucket::Get(const IoHash& HashKey, ZenCacheValue& OutValue)
+{
+	RwLock::SharedLockScope _(m_IndexLock);
+	auto					It = m_Index.find(HashKey);
+	if (It == m_Index.end())
+	{
+		return false;
+	}
+	size_t				 EntryIndex = It.value();
+	const BucketPayload& Payload	= m_Payloads[EntryIndex];
+	m_AccessTimes[EntryIndex]		= GcClock::TickCount();
+	DiskLocation Location			= Payload.Location;
+	OutValue.RawSize				= Payload.RawSize;
+	OutValue.RawHash				= Payload.RawHash;
+	if (Location.IsFlagSet(DiskLocation::kStandaloneFile))
+	{
+		// We don't need to hold the index lock when we read a standalone file
+		_.ReleaseNow();
+		OutValue.Value = GetStandaloneCacheValue(Location, HashKey);
+	}
+	else
+	{
+		OutValue.Value = GetInlineCacheValue(Location);
+	}
+	_.ReleaseNow();
+
+	if (!Location.IsFlagSet(DiskLocation::kStructured))
+	{
+		if (OutValue.RawHash == IoHash::Zero && OutValue.RawSize == 0 && OutValue.Value.GetSize() > 0)
+		{
+			if (Location.IsFlagSet(DiskLocation::kCompressed))
+			{
+				(void)CompressedBuffer::FromCompressed(SharedBuffer(OutValue.Value), OutValue.RawHash, OutValue.RawSize);
+			}
+			else
+			{
+				OutValue.RawHash = IoHash::HashBuffer(OutValue.Value);
+				OutValue.RawSize = OutValue.Value.GetSize();
+			}
+			RwLock::ExclusiveLockScope __(m_IndexLock);
+			if (auto WriteIt = m_Index.find(HashKey); WriteIt != m_Index.end())
+			{
+				BucketPayload& WritePayload = m_Payloads[WriteIt.value()];
+				WritePayload.RawHash		= OutValue.RawHash;
+				WritePayload.RawSize		= OutValue.RawSize;
+
+				m_LogFlushPosition = 0;	 // Force resave of index on exit
+			}
+		}
+	}
+
+	return (bool)OutValue.Value;
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::Put(const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	if (Value.Value.Size() >= m_LargeObjectThreshold)
+	{
+		return PutStandaloneCacheValue(HashKey, Value);
+	}
+	PutInlineCacheValue(HashKey, Value);
+}
+
+bool
+ZenCacheDiskLayer::CacheBucket::Drop()
+{
+	RwLock::ExclusiveLockScope _(m_IndexLock);
+
+	std::vector<std::unique_ptr<RwLock::ExclusiveLockScope>> ShardLocks;
+	ShardLocks.reserve(256);
+	for (RwLock& Lock : m_ShardedLocks)
+	{
+		ShardLocks.push_back(std::make_unique<RwLock::ExclusiveLockScope>(Lock));
+	}
+	m_BlockStore.Close();
+	m_SlogFile.Close();
+
+	bool Deleted = MoveAndDeleteDirectory(m_BucketDir);
+
+	m_Index.clear();
+	m_Payloads.clear();
+	m_AccessTimes.clear();
+	return Deleted;
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::Flush()
+{
+	m_BlockStore.Flush();
+
+	RwLock::SharedLockScope _(m_IndexLock);
+	m_SlogFile.Flush();
+	MakeIndexSnapshot();
+	SaveManifest();
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::SaveManifest()
+{
+	using namespace std::literals;
+
+	CbObjectWriter Writer;
+	Writer << "BucketId"sv << m_BucketId;
+
+	if (!m_Index.empty())
+	{
+		Writer.BeginArray("Timestamps"sv);
+		for (auto& Kv : m_Index)
+		{
+			const IoHash& Key		 = Kv.first;
+			GcClock::Tick AccessTime = m_AccessTimes[Kv.second];
+
+			Writer.BeginObject();
+			Writer << "Key"sv << Key;
+			Writer << "LastAccess"sv << AccessTime;
+			Writer.EndObject();
+		}
+		Writer.EndArray();
+
+		Writer.BeginArray("RawInfo"sv);
+		{
+			for (auto& Kv : m_Index)
+			{
+				const IoHash&		 Key	 = Kv.first;
+				const BucketPayload& Payload = m_Payloads[Kv.second];
+				if (Payload.RawHash != IoHash::Zero)
+				{
+					Writer.BeginObject();
+					Writer << "Key"sv << Key;
+					Writer << "RawHash"sv << Payload.RawHash;
+					Writer << "RawSize"sv << Payload.RawSize;
+					Writer.EndObject();
+				}
+			}
+		}
+		Writer.EndArray();
+	}
+
+	SaveCompactBinaryObject(m_BucketDir / "zen_manifest", Writer.Save());
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::Scrub(ScrubContext& Ctx)
+{
+	std::vector<IoHash>				BadKeys;
+	uint64_t						ChunkCount{0}, ChunkBytes{0};
+	std::vector<BlockStoreLocation> ChunkLocations;
+	std::vector<IoHash>				ChunkIndexToChunkHash;
+
+	auto ValidateEntry = [](const IoHash& Hash, ZenContentType ContentType, IoBuffer Buffer) {
+		if (ContentType == ZenContentType::kCbObject)
+		{
+			CbValidateError Error = ValidateCompactBinary(Buffer, CbValidateMode::All);
+			return Error == CbValidateError::None;
+		}
+		if (ContentType == ZenContentType::kCompressedBinary)
+		{
+			IoHash	 RawHash;
+			uint64_t RawSize;
+			if (!CompressedBuffer::ValidateCompressedHeader(Buffer, RawHash, RawSize))
+			{
+				return false;
+			}
+			if (RawHash != Hash)
+			{
+				return false;
+			}
+		}
+		return true;
+	};
+
+	RwLock::SharedLockScope _(m_IndexLock);
+
+	const size_t BlockChunkInitialCount = m_Index.size() / 4;
+	ChunkLocations.reserve(BlockChunkInitialCount);
+	ChunkIndexToChunkHash.reserve(BlockChunkInitialCount);
+
+	for (auto& Kv : m_Index)
+	{
+		const IoHash&		 HashKey = Kv.first;
+		const BucketPayload& Payload = m_Payloads[Kv.second];
+		const DiskLocation&	 Loc	 = Payload.Location;
+
+		if (Loc.IsFlagSet(DiskLocation::kStandaloneFile))
+		{
+			++ChunkCount;
+			ChunkBytes += Loc.Size();
+			if (Loc.GetContentType() == ZenContentType::kBinary)
+			{
+				ExtendablePathBuilder<256> DataFilePath;
+				BuildPath(DataFilePath, HashKey);
+
+				RwLock::SharedLockScope ValueLock(LockForHash(HashKey));
+
+				std::error_code Ec;
+				uintmax_t		size = std::filesystem::file_size(DataFilePath.ToPath(), Ec);
+				if (Ec)
+				{
+					BadKeys.push_back(HashKey);
+				}
+				if (size != Loc.Size())
+				{
+					BadKeys.push_back(HashKey);
+				}
+				continue;
+			}
+			IoBuffer Buffer = GetStandaloneCacheValue(Loc, HashKey);
+			if (!Buffer)
+			{
+				BadKeys.push_back(HashKey);
+				continue;
+			}
+			if (!ValidateEntry(HashKey, Loc.GetContentType(), Buffer))
+			{
+				BadKeys.push_back(HashKey);
+				continue;
+			}
+		}
+		else
+		{
+			ChunkLocations.emplace_back(Loc.GetBlockLocation(m_PayloadAlignment));
+			ChunkIndexToChunkHash.push_back(HashKey);
+			continue;
+		}
+	}
+
+	const auto ValidateSmallChunk = [&](size_t ChunkIndex, const void* Data, uint64_t Size) {
+		++ChunkCount;
+		ChunkBytes += Size;
+		const IoHash& Hash = ChunkIndexToChunkHash[ChunkIndex];
+		if (!Data)
+		{
+			// ChunkLocation out of range of stored blocks
+			BadKeys.push_back(Hash);
+			return;
+		}
+		IoBuffer Buffer(IoBuffer::Wrap, Data, Size);
+		if (!Buffer)
+		{
+			BadKeys.push_back(Hash);
+			return;
+		}
+		const BucketPayload& Payload	 = m_Payloads[m_Index.at(Hash)];
+		ZenContentType		 ContentType = Payload.Location.GetContentType();
+		if (!ValidateEntry(Hash, ContentType, Buffer))
+		{
+			BadKeys.push_back(Hash);
+			return;
+		}
+	};
+
+	const auto ValidateLargeChunk = [&](size_t ChunkIndex, BlockStoreFile& File, uint64_t Offset, uint64_t Size) {
+		++ChunkCount;
+		ChunkBytes += Size;
+		const IoHash& Hash = ChunkIndexToChunkHash[ChunkIndex];
+		// TODO: Add API to verify compressed buffer and possible structure data without having to memorymap the whole file
+		IoBuffer Buffer(IoBuffer::BorrowedFile, File.GetBasicFile().Handle(), Offset, Size);
+		if (!Buffer)
+		{
+			BadKeys.push_back(Hash);
+			return;
+		}
+		const BucketPayload& Payload	 = m_Payloads[m_Index.at(Hash)];
+		ZenContentType		 ContentType = Payload.Location.GetContentType();
+		if (!ValidateEntry(Hash, ContentType, Buffer))
+		{
+			BadKeys.push_back(Hash);
+			return;
+		}
+	};
+
+	m_BlockStore.IterateChunks(ChunkLocations, ValidateSmallChunk, ValidateLargeChunk);
+
+	_.ReleaseNow();
+
+	Ctx.ReportScrubbed(ChunkCount, ChunkBytes);
+
+	if (!BadKeys.empty())
+	{
+		ZEN_WARN("Scrubbing found {} bad chunks in '{}'", BadKeys.size(), m_BucketDir / m_BucketName);
+
+		if (Ctx.RunRecovery())
+		{
+			// Deal with bad chunks by removing them from our lookup map
+
+			std::vector<DiskIndexEntry> LogEntries;
+			LogEntries.reserve(BadKeys.size());
+
+			{
+				RwLock::ExclusiveLockScope __(m_IndexLock);
+				for (const IoHash& BadKey : BadKeys)
+				{
+					// Log a tombstone and delete the in-memory index for the bad entry
+					const auto			 It		  = m_Index.find(BadKey);
+					const BucketPayload& Payload  = m_Payloads[It->second];
+					DiskLocation		 Location = Payload.Location;
+					Location.Flags |= DiskLocation::kTombStone;
+					LogEntries.push_back(DiskIndexEntry{.Key = BadKey, .Location = Location});
+					m_Index.erase(BadKey);
+				}
+			}
+			for (const DiskIndexEntry& Entry : LogEntries)
+			{
+				if (Entry.Location.IsFlagSet(DiskLocation::kStandaloneFile))
+				{
+					ExtendablePathBuilder<256> Path;
+					BuildPath(Path, Entry.Key);
+					fs::path				   FilePath = Path.ToPath();
+					RwLock::ExclusiveLockScope ValueLock(LockForHash(Entry.Key));
+					if (fs::is_regular_file(FilePath))
+					{
+						ZEN_DEBUG("deleting bad standalone cache file '{}'", Path.ToUtf8());
+						std::error_code Ec;
+						fs::remove(FilePath, Ec);  // We don't care if we fail, we are no longer tracking this file...
+					}
+					m_TotalStandaloneSize.fetch_sub(Entry.Location.Size(), std::memory_order::relaxed);
+				}
+			}
+			m_SlogFile.Append(LogEntries);
+
+			// Clean up m_AccessTimes and m_Payloads vectors
+			{
+				std::vector<BucketPayload> Payloads;
+				std::vector<AccessTime>	   AccessTimes;
+				IndexMap				   Index;
+
+				{
+					RwLock::ExclusiveLockScope __(m_IndexLock);
+					size_t					   EntryCount = m_Index.size();
+					Payloads.reserve(EntryCount);
+					AccessTimes.reserve(EntryCount);
+					Index.reserve(EntryCount);
+					for (auto It : m_Index)
+					{
+						size_t EntryIndex = Payloads.size();
+						Payloads.push_back(m_Payloads[EntryIndex]);
+						AccessTimes.push_back(m_AccessTimes[EntryIndex]);
+						Index.insert({It.first, EntryIndex});
+					}
+					m_Index.swap(Index);
+					m_Payloads.swap(Payloads);
+					m_AccessTimes.swap(AccessTimes);
+				}
+			}
+		}
+	}
+
+	// Let whomever it concerns know about the bad chunks. This could
+	// be used to invalidate higher level data structures more efficiently
+	// than a full validation pass might be able to do
+	Ctx.ReportBadCidChunks(BadKeys);
+
+	ZEN_INFO("cache bucket scrubbed: {} chunks ({})", ChunkCount, NiceBytes(ChunkBytes));
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::GatherReferences(GcContext& GcCtx)
+{
+	ZEN_TRACE_CPU("Z$::DiskLayer::CacheBucket::GatherReferences");
+
+	uint64_t WriteBlockTimeUs		 = 0;
+	uint64_t WriteBlockLongestTimeUs = 0;
+	uint64_t ReadBlockTimeUs		 = 0;
+	uint64_t ReadBlockLongestTimeUs	 = 0;
+
+	Stopwatch  TotalTimer;
+	const auto _ = MakeGuard([&] {
+		ZEN_DEBUG("gathered references from '{}' in {} write lock: {} ({}), read lock: {} ({})",
+				  m_BucketDir / m_BucketName,
+				  NiceTimeSpanMs(TotalTimer.GetElapsedTimeMs()),
+				  NiceLatencyNs(WriteBlockTimeUs),
+				  NiceLatencyNs(WriteBlockLongestTimeUs),
+				  NiceLatencyNs(ReadBlockTimeUs),
+				  NiceLatencyNs(ReadBlockLongestTimeUs));
+	});
+
+	const GcClock::TimePoint ExpireTime = GcCtx.ExpireTime();
+
+	const GcClock::Tick ExpireTicks = ExpireTime.time_since_epoch().count();
+
+	IndexMap				   Index;
+	std::vector<AccessTime>	   AccessTimes;
+	std::vector<BucketPayload> Payloads;
+	{
+		RwLock::SharedLockScope __(m_IndexLock);
+		Stopwatch				Timer;
+		const auto				___ = MakeGuard([&] {
+			 uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+			 WriteBlockTimeUs += ElapsedUs;
+			 WriteBlockLongestTimeUs = std::max(ElapsedUs, WriteBlockLongestTimeUs);
+		 });
+		Index						= m_Index;
+		AccessTimes					= m_AccessTimes;
+		Payloads					= m_Payloads;
+	}
+
+	std::vector<IoHash> ExpiredKeys;
+	ExpiredKeys.reserve(1024);
+
+	std::vector<IoHash> Cids;
+	Cids.reserve(1024);
+
+	for (const auto& Entry : Index)
+	{
+		const IoHash& Key		 = Entry.first;
+		GcClock::Tick AccessTime = AccessTimes[Entry.second];
+		if (AccessTime < ExpireTicks)
+		{
+			ExpiredKeys.push_back(Key);
+			continue;
+		}
+
+		const DiskLocation& Loc = Payloads[Entry.second].Location;
+
+		if (Loc.IsFlagSet(DiskLocation::kStructured))
+		{
+			if (Cids.size() > 1024)
+			{
+				GcCtx.AddRetainedCids(Cids);
+				Cids.clear();
+			}
+
+			IoBuffer Buffer;
+			{
+				RwLock::SharedLockScope __(m_IndexLock);
+				Stopwatch				Timer;
+				const auto				___ = MakeGuard([&] {
+					 uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+					 WriteBlockTimeUs += ElapsedUs;
+					 WriteBlockLongestTimeUs = std::max(ElapsedUs, WriteBlockLongestTimeUs);
+				 });
+				if (Loc.IsFlagSet(DiskLocation::kStandaloneFile))
+				{
+					// We don't need to hold the index lock when we read a standalone file
+					__.ReleaseNow();
+					if (Buffer = GetStandaloneCacheValue(Loc, Key); !Buffer)
+					{
+						continue;
+					}
+				}
+				else if (Buffer = GetInlineCacheValue(Loc); !Buffer)
+				{
+					continue;
+				}
+			}
+
+			ZEN_ASSERT(Buffer);
+			ZEN_ASSERT(Buffer.GetContentType() == ZenContentType::kCbObject);
+			CbObject Obj(SharedBuffer{Buffer});
+			Obj.IterateAttachments([&Cids](CbFieldView Field) { Cids.push_back(Field.AsAttachment()); });
+		}
+	}
+
+	GcCtx.AddRetainedCids(Cids);
+	GcCtx.SetExpiredCacheKeys(m_BucketDir.string(), std::move(ExpiredKeys));
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::CollectGarbage(GcContext& GcCtx)
+{
+	ZEN_TRACE_CPU("Z$::DiskLayer::CacheBucket::CollectGarbage");
+
+	ZEN_DEBUG("collecting garbage from '{}'", m_BucketDir / m_BucketName);
+
+	Stopwatch TotalTimer;
+	uint64_t  WriteBlockTimeUs		  = 0;
+	uint64_t  WriteBlockLongestTimeUs = 0;
+	uint64_t  ReadBlockTimeUs		  = 0;
+	uint64_t  ReadBlockLongestTimeUs  = 0;
+	uint64_t  TotalChunkCount		  = 0;
+	uint64_t  DeletedSize			  = 0;
+	uint64_t  OldTotalSize			  = TotalSize();
+
+	std::unordered_set<IoHash> DeletedChunks;
+	uint64_t				   MovedCount = 0;
+
+	const auto _ = MakeGuard([&] {
+		ZEN_DEBUG(
+			"garbage collect from '{}' DONE after {}, write lock: {} ({}), read lock: {} ({}), collected {} bytes, deleted {} and moved "
+			"{} "
+			"of {} "
+			"entires ({}).",
+			m_BucketDir / m_BucketName,
+			NiceTimeSpanMs(TotalTimer.GetElapsedTimeMs()),
+			NiceLatencyNs(WriteBlockTimeUs),
+			NiceLatencyNs(WriteBlockLongestTimeUs),
+			NiceLatencyNs(ReadBlockTimeUs),
+			NiceLatencyNs(ReadBlockLongestTimeUs),
+			NiceBytes(DeletedSize),
+			DeletedChunks.size(),
+			MovedCount,
+			TotalChunkCount,
+			NiceBytes(OldTotalSize));
+		RwLock::SharedLockScope _(m_IndexLock);
+		SaveManifest();
+	});
+
+	m_SlogFile.Flush();
+
+	std::span<const IoHash> ExpiredCacheKeys = GcCtx.ExpiredCacheKeys(m_BucketDir.string());
+	std::vector<IoHash>		DeleteCacheKeys;
+	DeleteCacheKeys.reserve(ExpiredCacheKeys.size());
+	GcCtx.FilterCids(ExpiredCacheKeys, [&](const IoHash& ChunkHash, bool Keep) {
+		if (Keep)
+		{
+			return;
+		}
+		DeleteCacheKeys.push_back(ChunkHash);
+	});
+	if (DeleteCacheKeys.empty())
+	{
+		ZEN_DEBUG("garbage collect SKIPPED, for '{}', no expired cache keys found", m_BucketDir / m_BucketName);
+		return;
+	}
+
+	auto __ = MakeGuard([&]() {
+		if (!DeletedChunks.empty())
+		{
+			// Clean up m_AccessTimes and m_Payloads vectors
+			std::vector<BucketPayload> Payloads;
+			std::vector<AccessTime>	   AccessTimes;
+			IndexMap				   Index;
+
+			{
+				RwLock::ExclusiveLockScope _(m_IndexLock);
+				Stopwatch				   Timer;
+				const auto				   ___		  = MakeGuard([&] {
+					   uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+					   WriteBlockTimeUs += ElapsedUs;
+					   WriteBlockLongestTimeUs = std::max(ElapsedUs, WriteBlockLongestTimeUs);
+				   });
+				size_t					   EntryCount = m_Index.size();
+				Payloads.reserve(EntryCount);
+				AccessTimes.reserve(EntryCount);
+				Index.reserve(EntryCount);
+				for (auto It : m_Index)
+				{
+					size_t EntryIndex = Payloads.size();
+					Payloads.push_back(m_Payloads[EntryIndex]);
+					AccessTimes.push_back(m_AccessTimes[EntryIndex]);
+					Index.insert({It.first, EntryIndex});
+				}
+				m_Index.swap(Index);
+				m_Payloads.swap(Payloads);
+				m_AccessTimes.swap(AccessTimes);
+			}
+			GcCtx.AddDeletedCids(std::vector<IoHash>(DeletedChunks.begin(), DeletedChunks.end()));
+		}
+	});
+
+	std::vector<DiskIndexEntry>		 ExpiredStandaloneEntries;
+	IndexMap						 Index;
+	BlockStore::ReclaimSnapshotState BlockStoreState;
+	{
+		RwLock::SharedLockScope __(m_IndexLock);
+		Stopwatch				Timer;
+		const auto				____ = MakeGuard([&] {
+			 uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+			 WriteBlockTimeUs += ElapsedUs;
+			 WriteBlockLongestTimeUs = std::max(ElapsedUs, WriteBlockLongestTimeUs);
+		 });
+		if (m_Index.empty())
+		{
+			ZEN_DEBUG("garbage collect SKIPPED, for '{}', container is empty", m_BucketDir / m_BucketName);
+			return;
+		}
+		BlockStoreState = m_BlockStore.GetReclaimSnapshotState();
+
+		SaveManifest();
+		Index = m_Index;
+
+		for (const IoHash& Key : DeleteCacheKeys)
+		{
+			if (auto It = Index.find(Key); It != Index.end())
+			{
+				const BucketPayload& Payload = m_Payloads[It->second];
+				DiskIndexEntry		 Entry	 = {.Key = It->first, .Location = Payload.Location};
+				if (Entry.Location.Flags & DiskLocation::kStandaloneFile)
+				{
+					Entry.Location.Flags |= DiskLocation::kTombStone;
+					ExpiredStandaloneEntries.push_back(Entry);
+				}
+			}
+		}
+		if (GcCtx.IsDeletionMode())
+		{
+			for (const auto& Entry : ExpiredStandaloneEntries)
+			{
+				m_Index.erase(Entry.Key);
+				m_TotalStandaloneSize.fetch_sub(Entry.Location.Size(), std::memory_order::relaxed);
+				DeletedChunks.insert(Entry.Key);
+			}
+			m_SlogFile.Append(ExpiredStandaloneEntries);
+		}
+	}
+
+	if (GcCtx.IsDeletionMode())
+	{
+		std::error_code			   Ec;
+		ExtendablePathBuilder<256> Path;
+
+		for (const auto& Entry : ExpiredStandaloneEntries)
+		{
+			const IoHash&		Key = Entry.Key;
+			const DiskLocation& Loc = Entry.Location;
+
+			Path.Reset();
+			BuildPath(Path, Key);
+			fs::path FilePath = Path.ToPath();
+
+			{
+				RwLock::SharedLockScope __(m_IndexLock);
+				Stopwatch				Timer;
+				const auto				____ = MakeGuard([&] {
+					 uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+					 WriteBlockTimeUs += ElapsedUs;
+					 WriteBlockLongestTimeUs = std::max(ElapsedUs, WriteBlockLongestTimeUs);
+				 });
+				if (m_Index.contains(Key))
+				{
+					// Someone added it back, let the file on disk be
+					ZEN_DEBUG("skipping z$ delete standalone of file '{}' FAILED, it has been added back", Path.ToUtf8());
+					continue;
+				}
+				__.ReleaseNow();
+
+				RwLock::ExclusiveLockScope ValueLock(LockForHash(Key));
+				if (fs::is_regular_file(FilePath))
+				{
+					ZEN_DEBUG("deleting standalone cache file '{}'", Path.ToUtf8());
+					fs::remove(FilePath, Ec);
+				}
+			}
+
+			if (Ec)
+			{
+				ZEN_WARN("delete expired z$ standalone file '{}' FAILED, reason: '{}'", Path.ToUtf8(), Ec.message());
+				Ec.clear();
+				DiskLocation RestoreLocation = Loc;
+				RestoreLocation.Flags &= ~DiskLocation::kTombStone;
+
+				RwLock::ExclusiveLockScope __(m_IndexLock);
+				Stopwatch				   Timer;
+				const auto				   ___ = MakeGuard([&] {
+					uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+					ReadBlockTimeUs += ElapsedUs;
+					ReadBlockLongestTimeUs = std::max(ElapsedUs, ReadBlockLongestTimeUs);
+				});
+				if (m_Index.contains(Key))
+				{
+					continue;
+				}
+				m_SlogFile.Append(DiskIndexEntry{.Key = Key, .Location = RestoreLocation});
+				size_t EntryIndex = m_Payloads.size();
+				m_Payloads.emplace_back(BucketPayload{.Location = RestoreLocation});
+				m_AccessTimes.emplace_back(GcClock::TickCount());
+				m_Index.insert({Key, EntryIndex});
+				m_TotalStandaloneSize.fetch_add(RestoreLocation.Size(), std::memory_order::relaxed);
+				DeletedChunks.erase(Key);
+				continue;
+			}
+			DeletedSize += Entry.Location.Size();
+		}
+	}
+
+	TotalChunkCount = Index.size();
+
+	std::vector<IoHash> TotalChunkHashes;
+	TotalChunkHashes.reserve(TotalChunkCount);
+	for (const auto& Entry : Index)
+	{
+		const DiskLocation& Location = m_Payloads[Entry.second].Location;
+
+		if (Location.Flags & DiskLocation::kStandaloneFile)
+		{
+			continue;
+		}
+		TotalChunkHashes.push_back(Entry.first);
+	}
+
+	if (TotalChunkHashes.empty())
+	{
+		return;
+	}
+	TotalChunkCount = TotalChunkHashes.size();
+
+	std::vector<BlockStoreLocation> ChunkLocations;
+	BlockStore::ChunkIndexArray		KeepChunkIndexes;
+	std::vector<IoHash>				ChunkIndexToChunkHash;
+	ChunkLocations.reserve(TotalChunkCount);
+	ChunkLocations.reserve(TotalChunkCount);
+	ChunkIndexToChunkHash.reserve(TotalChunkCount);
+
+	GcCtx.FilterCids(TotalChunkHashes, [&](const IoHash& ChunkHash, bool Keep) {
+		auto				KeyIt		 = Index.find(ChunkHash);
+		const DiskLocation& DiskLocation = m_Payloads[KeyIt->second].Location;
+		BlockStoreLocation	Location	 = DiskLocation.GetBlockLocation(m_PayloadAlignment);
+		size_t				ChunkIndex	 = ChunkLocations.size();
+		ChunkLocations.push_back(Location);
+		ChunkIndexToChunkHash[ChunkIndex] = ChunkHash;
+		if (Keep)
+		{
+			KeepChunkIndexes.push_back(ChunkIndex);
+		}
+	});
+
+	size_t DeleteCount = TotalChunkCount - KeepChunkIndexes.size();
+
+	const bool PerformDelete = GcCtx.IsDeletionMode() && GcCtx.CollectSmallObjects();
+	if (!PerformDelete)
+	{
+		m_BlockStore.ReclaimSpace(BlockStoreState, ChunkLocations, KeepChunkIndexes, m_PayloadAlignment, true);
+		uint64_t CurrentTotalSize = TotalSize();
+		ZEN_DEBUG("garbage collect from '{}' DISABLED, found {} chunks of total {} {}",
+				  m_BucketDir / m_BucketName,
+				  DeleteCount,
+				  TotalChunkCount,
+				  NiceBytes(CurrentTotalSize));
+		return;
+	}
+
+	m_BlockStore.ReclaimSpace(
+		BlockStoreState,
+		ChunkLocations,
+		KeepChunkIndexes,
+		m_PayloadAlignment,
+		false,
+		[&](const BlockStore::MovedChunksArray& MovedChunks, const BlockStore::ChunkIndexArray& RemovedChunks) {
+			std::vector<DiskIndexEntry> LogEntries;
+			LogEntries.reserve(MovedChunks.size() + RemovedChunks.size());
+			for (const auto& Entry : MovedChunks)
+			{
+				size_t					  ChunkIndex	  = Entry.first;
+				const BlockStoreLocation& NewLocation	  = Entry.second;
+				const IoHash&			  ChunkHash		  = ChunkIndexToChunkHash[ChunkIndex];
+				const BucketPayload&	  OldPayload	  = m_Payloads[Index[ChunkHash]];
+				const DiskLocation&		  OldDiskLocation = OldPayload.Location;
+				LogEntries.push_back(
+					{.Key = ChunkHash, .Location = DiskLocation(NewLocation, m_PayloadAlignment, OldDiskLocation.GetFlags())});
+			}
+			for (const size_t ChunkIndex : RemovedChunks)
+			{
+				const IoHash&		 ChunkHash		 = ChunkIndexToChunkHash[ChunkIndex];
+				const BucketPayload& OldPayload		 = m_Payloads[Index[ChunkHash]];
+				const DiskLocation&	 OldDiskLocation = OldPayload.Location;
+				LogEntries.push_back({.Key		= ChunkHash,
+									  .Location = DiskLocation(OldDiskLocation.GetBlockLocation(m_PayloadAlignment),
+															   m_PayloadAlignment,
+															   OldDiskLocation.GetFlags() | DiskLocation::kTombStone)});
+				DeletedChunks.insert(ChunkHash);
+			}
+
+			m_SlogFile.Append(LogEntries);
+			m_SlogFile.Flush();
+			{
+				RwLock::ExclusiveLockScope __(m_IndexLock);
+				Stopwatch				   Timer;
+				const auto				   ____ = MakeGuard([&] {
+					uint64_t ElapsedUs = Timer.GetElapsedTimeUs();
+					ReadBlockTimeUs += ElapsedUs;
+					ReadBlockLongestTimeUs = std::max(ElapsedUs, ReadBlockLongestTimeUs);
+				});
+				for (const DiskIndexEntry& Entry : LogEntries)
+				{
+					if (Entry.Location.GetFlags() & DiskLocation::kTombStone)
+					{
+						m_Index.erase(Entry.Key);
+						continue;
+					}
+					m_Payloads[m_Index[Entry.Key]].Location = Entry.Location;
+				}
+			}
+		},
+		[&]() { return GcCtx.CollectSmallObjects(); });
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::UpdateAccessTimes(const std::vector<zen::access_tracking::KeyAccessTime>& AccessTimes)
+{
+	using namespace access_tracking;
+
+	for (const KeyAccessTime& KeyTime : AccessTimes)
+	{
+		if (auto It = m_Index.find(KeyTime.Key); It != m_Index.end())
+		{
+			size_t EntryIndex = It.value();
+			ZEN_ASSERT_SLOW(EntryIndex < m_AccessTimes.size());
+			m_AccessTimes[EntryIndex] = KeyTime.LastAccess;
+		}
+	}
+}
+
+uint64_t
+ZenCacheDiskLayer::CacheBucket::EntryCount() const
+{
+	RwLock::SharedLockScope _(m_IndexLock);
+	return static_cast<uint64_t>(m_Index.size());
+}
+
+CacheValueDetails::ValueDetails
+ZenCacheDiskLayer::CacheBucket::GetValueDetails(const IoHash& Key, size_t Index) const
+{
+	std::vector<IoHash>	 Attachments;
+	const BucketPayload& Payload = m_Payloads[Index];
+	if (Payload.Location.IsFlagSet(DiskLocation::kStructured))
+	{
+		IoBuffer Value = Payload.Location.IsFlagSet(DiskLocation::kStandaloneFile) ? GetStandaloneCacheValue(Payload.Location, Key)
+																				   : GetInlineCacheValue(Payload.Location);
+		CbObject Obj(SharedBuffer{Value});
+		Obj.IterateAttachments([&Attachments](CbFieldView Field) { Attachments.emplace_back(Field.AsAttachment()); });
+	}
+	return CacheValueDetails::ValueDetails{.Size		= Payload.Location.Size(),
+										   .RawSize		= Payload.RawSize,
+										   .RawHash		= Payload.RawHash,
+										   .LastAccess	= m_AccessTimes[Index],
+										   .Attachments = std::move(Attachments),
+										   .ContentType = Payload.Location.GetContentType()};
+}
+
+CacheValueDetails::BucketDetails
+ZenCacheDiskLayer::CacheBucket::GetValueDetails(const std::string_view ValueFilter) const
+{
+	CacheValueDetails::BucketDetails Details;
+	RwLock::SharedLockScope			 _(m_IndexLock);
+	if (ValueFilter.empty())
+	{
+		Details.Values.reserve(m_Index.size());
+		for (const auto& It : m_Index)
+		{
+			Details.Values.insert_or_assign(It.first, GetValueDetails(It.first, It.second));
+		}
+	}
+	else
+	{
+		IoHash Key = IoHash::FromHexString(ValueFilter);
+		if (auto It = m_Index.find(Key); It != m_Index.end())
+		{
+			Details.Values.insert_or_assign(It->first, GetValueDetails(It->first, It->second));
+		}
+	}
+	return Details;
+}
+
+void
+ZenCacheDiskLayer::CollectGarbage(GcContext& GcCtx)
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		CacheBucket& Bucket = *Kv.second;
+		Bucket.CollectGarbage(GcCtx);
+	}
+}
+
+void
+ZenCacheDiskLayer::UpdateAccessTimes(const zen::access_tracking::AccessTimes& AccessTimes)
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (const auto& Kv : AccessTimes.Buckets)
+	{
+		if (auto It = m_Buckets.find(Kv.first); It != m_Buckets.end())
+		{
+			CacheBucket& Bucket = *It->second;
+			Bucket.UpdateAccessTimes(Kv.second);
+		}
+	}
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::PutStandaloneCacheValue(const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	uint64_t NewFileSize = Value.Value.Size();
+
+	TemporaryFile DataFile;
+
+	std::error_code Ec;
+	DataFile.CreateTemporary(m_BucketDir.c_str(), Ec);
+	if (Ec)
+	{
+		throw std::system_error(Ec, fmt::format("Failed to open temporary file for put in '{}'", m_BucketDir));
+	}
+
+	bool CleanUpTempFile = false;
+	auto __				 = MakeGuard([&] {
+		 if (CleanUpTempFile)
+		 {
+			 std::error_code Ec;
+			 std::filesystem::remove(DataFile.GetPath(), Ec);
+			 if (Ec)
+			 {
+				 ZEN_WARN("Failed to clean up temporary file '{}' for put in '{}', reason '{}'",
+						  DataFile.GetPath(),
+						  m_BucketDir,
+						  Ec.message());
+			 }
+		 }
+	 });
+
+	DataFile.WriteAll(Value.Value, Ec);
+	if (Ec)
+	{
+		throw std::system_error(Ec,
+								fmt::format("Failed to write payload ({} bytes) to temporary file '{}' for put in '{}'",
+											NiceBytes(NewFileSize),
+											DataFile.GetPath().string(),
+											m_BucketDir));
+	}
+
+	ExtendablePathBuilder<256> DataFilePath;
+	BuildPath(DataFilePath, HashKey);
+	std::filesystem::path FsPath{DataFilePath.ToPath()};
+
+	RwLock::ExclusiveLockScope ValueLock(LockForHash(HashKey));
+
+	// We do a speculative remove of the file instead of probing with a exists call and check the error code instead
+	std::filesystem::remove(FsPath, Ec);
+	if (Ec)
+	{
+		if (Ec.value() != ENOENT)
+		{
+			ZEN_WARN("Failed to remove file '{}' for put in '{}', reason: '{}', retrying.", FsPath, m_BucketDir, Ec.message());
+			Sleep(100);
+			Ec.clear();
+			std::filesystem::remove(FsPath, Ec);
+			if (Ec && Ec.value() != ENOENT)
+			{
+				throw std::system_error(Ec, fmt::format("Failed to remove file '{}' for put in '{}'", FsPath, m_BucketDir));
+			}
+		}
+	}
+
+	DataFile.MoveTemporaryIntoPlace(FsPath, Ec);
+	if (Ec)
+	{
+		CreateDirectories(FsPath.parent_path());
+		Ec.clear();
+
+		// Try again
+		DataFile.MoveTemporaryIntoPlace(FsPath, Ec);
+		if (Ec)
+		{
+			ZEN_WARN("Failed to finalize file '{}', moving from '{}' for put in '{}', reason: '{}', retrying.",
+					 FsPath,
+					 DataFile.GetPath(),
+					 m_BucketDir,
+					 Ec.message());
+			Sleep(100);
+			Ec.clear();
+			DataFile.MoveTemporaryIntoPlace(FsPath, Ec);
+			if (Ec)
+			{
+				throw std::system_error(
+					Ec,
+					fmt::format("Failed to finalize file '{}', moving from '{}' for put in '{}'", FsPath, DataFile.GetPath(), m_BucketDir));
+			}
+		}
+	}
+
+	// Once we have called MoveTemporaryIntoPlace automatic clean up the temp file
+	// will be disabled as the file handle has already been closed
+	CleanUpTempFile = false;
+
+	uint8_t EntryFlags = DiskLocation::kStandaloneFile;
+
+	if (Value.Value.GetContentType() == ZenContentType::kCbObject)
+	{
+		EntryFlags |= DiskLocation::kStructured;
+	}
+	else if (Value.Value.GetContentType() == ZenContentType::kCompressedBinary)
+	{
+		EntryFlags |= DiskLocation::kCompressed;
+	}
+
+	DiskLocation Loc(NewFileSize, EntryFlags);
+
+	RwLock::ExclusiveLockScope _(m_IndexLock);
+	if (auto It = m_Index.find(HashKey); It == m_Index.end())
+	{
+		// Previously unknown object
+		size_t EntryIndex = m_Payloads.size();
+		m_Payloads.emplace_back(BucketPayload{.Location = Loc, .RawSize = Value.RawSize, .RawHash = Value.RawHash});
+		m_AccessTimes.emplace_back(GcClock::TickCount());
+		m_Index.insert_or_assign(HashKey, EntryIndex);
+	}
+	else
+	{
+		// TODO: should check if write is idempotent and bail out if it is?
+		size_t EntryIndex = It.value();
+		ZEN_ASSERT_SLOW(EntryIndex < m_AccessTimes.size());
+		m_Payloads[EntryIndex] = BucketPayload{.Location = Loc, .RawSize = Value.RawSize, .RawHash = Value.RawHash};
+		m_AccessTimes.emplace_back(GcClock::TickCount());
+		m_TotalStandaloneSize.fetch_sub(Loc.Size(), std::memory_order::relaxed);
+	}
+
+	m_SlogFile.Append({.Key = HashKey, .Location = Loc});
+	m_TotalStandaloneSize.fetch_add(NewFileSize, std::memory_order::relaxed);
+}
+
+void
+ZenCacheDiskLayer::CacheBucket::PutInlineCacheValue(const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	uint8_t EntryFlags = 0;
+
+	if (Value.Value.GetContentType() == ZenContentType::kCbObject)
+	{
+		EntryFlags |= DiskLocation::kStructured;
+	}
+	else if (Value.Value.GetContentType() == ZenContentType::kCompressedBinary)
+	{
+		EntryFlags |= DiskLocation::kCompressed;
+	}
+
+	m_BlockStore.WriteChunk(Value.Value.Data(), Value.Value.Size(), m_PayloadAlignment, [&](const BlockStoreLocation& BlockStoreLocation) {
+		DiskLocation Location(BlockStoreLocation, m_PayloadAlignment, EntryFlags);
+		m_SlogFile.Append({.Key = HashKey, .Location = Location});
+
+		RwLock::ExclusiveLockScope _(m_IndexLock);
+		if (auto It = m_Index.find(HashKey); It != m_Index.end())
+		{
+			// TODO: should check if write is idempotent and bail out if it is?
+			// this would requiring comparing contents on disk unless we add a
+			// content hash to the index entry
+			size_t EntryIndex = It.value();
+			ZEN_ASSERT_SLOW(EntryIndex < m_AccessTimes.size());
+			m_Payloads[EntryIndex]	  = (BucketPayload{.Location = Location, .RawSize = Value.RawSize, .RawHash = Value.RawHash});
+			m_AccessTimes[EntryIndex] = GcClock::TickCount();
+		}
+		else
+		{
+			size_t EntryIndex = m_Payloads.size();
+			m_Payloads.emplace_back(BucketPayload{.Location = Location, .RawSize = Value.RawSize, .RawHash = Value.RawHash});
+			m_AccessTimes.emplace_back(GcClock::TickCount());
+			m_Index.insert_or_assign(HashKey, EntryIndex);
+		}
+	});
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+ZenCacheDiskLayer::ZenCacheDiskLayer(const std::filesystem::path& RootDir) : m_RootDir(RootDir)
+{
+}
+
+ZenCacheDiskLayer::~ZenCacheDiskLayer() = default;
+
+bool
+ZenCacheDiskLayer::Get(std::string_view InBucket, const IoHash& HashKey, ZenCacheValue& OutValue)
+{
+	const auto	 BucketName = std::string(InBucket);
+	CacheBucket* Bucket		= nullptr;
+
+	{
+		RwLock::SharedLockScope _(m_Lock);
+
+		auto It = m_Buckets.find(BucketName);
+
+		if (It != m_Buckets.end())
+		{
+			Bucket = It->second.get();
+		}
+	}
+
+	if (Bucket == nullptr)
+	{
+		// Bucket needs to be opened/created
+
+		RwLock::ExclusiveLockScope _(m_Lock);
+
+		if (auto It = m_Buckets.find(BucketName); It != m_Buckets.end())
+		{
+			Bucket = It->second.get();
+		}
+		else
+		{
+			auto InsertResult = m_Buckets.emplace(BucketName, std::make_unique<CacheBucket>(BucketName));
+			Bucket			  = InsertResult.first->second.get();
+
+			std::filesystem::path BucketPath = m_RootDir;
+			BucketPath /= BucketName;
+
+			if (!Bucket->OpenOrCreate(BucketPath))
+			{
+				m_Buckets.erase(InsertResult.first);
+				return false;
+			}
+		}
+	}
+
+	ZEN_ASSERT(Bucket != nullptr);
+	return Bucket->Get(HashKey, OutValue);
+}
+
+void
+ZenCacheDiskLayer::Put(std::string_view InBucket, const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	const auto	 BucketName = std::string(InBucket);
+	CacheBucket* Bucket		= nullptr;
+
+	{
+		RwLock::SharedLockScope _(m_Lock);
+
+		auto It = m_Buckets.find(BucketName);
+
+		if (It != m_Buckets.end())
+		{
+			Bucket = It->second.get();
+		}
+	}
+
+	if (Bucket == nullptr)
+	{
+		// New bucket needs to be created
+
+		RwLock::ExclusiveLockScope _(m_Lock);
+
+		if (auto It = m_Buckets.find(BucketName); It != m_Buckets.end())
+		{
+			Bucket = It->second.get();
+		}
+		else
+		{
+			auto InsertResult = m_Buckets.emplace(BucketName, std::make_unique<CacheBucket>(BucketName));
+			Bucket			  = InsertResult.first->second.get();
+
+			std::filesystem::path BucketPath = m_RootDir;
+			BucketPath /= BucketName;
+
+			try
+			{
+				if (!Bucket->OpenOrCreate(BucketPath))
+				{
+					ZEN_WARN("Found directory '{}' in our base directory '{}' but it is not a valid bucket", BucketName, m_RootDir);
+					m_Buckets.erase(InsertResult.first);
+					return;
+				}
+			}
+			catch (const std::exception& Err)
+			{
+				ZEN_ERROR("creating bucket '{}' in '{}' FAILED, reason: '{}'", BucketName, BucketPath, Err.what());
+				return;
+			}
+		}
+	}
+
+	ZEN_ASSERT(Bucket != nullptr);
+
+	Bucket->Put(HashKey, Value);
+}
+
+void
+ZenCacheDiskLayer::DiscoverBuckets()
+{
+	DirectoryContent DirContent;
+	GetDirectoryContent(m_RootDir, DirectoryContent::IncludeDirsFlag, DirContent);
+
+	// Initialize buckets
+
+	RwLock::ExclusiveLockScope _(m_Lock);
+
+	for (const std::filesystem::path& BucketPath : DirContent.Directories)
+	{
+		const std::string BucketName = PathToUtf8(BucketPath.stem());
+		// New bucket needs to be created
+		if (auto It = m_Buckets.find(BucketName); It != m_Buckets.end())
+		{
+			continue;
+		}
+
+		auto		 InsertResult = m_Buckets.emplace(BucketName, std::make_unique<CacheBucket>(BucketName));
+		CacheBucket& Bucket		  = *InsertResult.first->second;
+
+		try
+		{
+			if (!Bucket.OpenOrCreate(BucketPath, /* AllowCreate */ false))
+			{
+				ZEN_WARN("Found directory '{}' in our base directory '{}' but it is not a valid bucket", BucketName, m_RootDir);
+
+				m_Buckets.erase(InsertResult.first);
+				continue;
+			}
+		}
+		catch (const std::exception& Err)
+		{
+			ZEN_ERROR("creating bucket '{}' in '{}' FAILED, reason: '{}'", BucketName, BucketPath, Err.what());
+			return;
+		}
+		ZEN_INFO("Discovered bucket '{}'", BucketName);
+	}
+}
+
+bool
+ZenCacheDiskLayer::DropBucket(std::string_view InBucket)
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+
+	auto It = m_Buckets.find(std::string(InBucket));
+
+	if (It != m_Buckets.end())
+	{
+		CacheBucket& Bucket = *It->second;
+		m_DroppedBuckets.push_back(std::move(It->second));
+		m_Buckets.erase(It);
+
+		return Bucket.Drop();
+	}
+
+	// Make sure we remove the folder even if we don't know about the bucket
+	std::filesystem::path BucketPath = m_RootDir;
+	BucketPath /= std::string(InBucket);
+	return MoveAndDeleteDirectory(BucketPath);
+}
+
+bool
+ZenCacheDiskLayer::Drop()
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+
+	std::vector<std::unique_ptr<CacheBucket>> Buckets;
+	Buckets.reserve(m_Buckets.size());
+	while (!m_Buckets.empty())
+	{
+		const auto&	 It		= m_Buckets.begin();
+		CacheBucket& Bucket = *It->second;
+		m_DroppedBuckets.push_back(std::move(It->second));
+		m_Buckets.erase(It->first);
+		if (!Bucket.Drop())
+		{
+			return false;
+		}
+	}
+	return MoveAndDeleteDirectory(m_RootDir);
+}
+
+void
+ZenCacheDiskLayer::Flush()
+{
+	std::vector<CacheBucket*> Buckets;
+
+	{
+		RwLock::SharedLockScope _(m_Lock);
+		Buckets.reserve(m_Buckets.size());
+		for (auto& Kv : m_Buckets)
+		{
+			CacheBucket* Bucket = Kv.second.get();
+			Buckets.push_back(Bucket);
+		}
+	}
+
+	for (auto& Bucket : Buckets)
+	{
+		Bucket->Flush();
+	}
+}
+
+void
+ZenCacheDiskLayer::Scrub(ScrubContext& Ctx)
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		CacheBucket& Bucket = *Kv.second;
+		Bucket.Scrub(Ctx);
+	}
+}
+
+void
+ZenCacheDiskLayer::GatherReferences(GcContext& GcCtx)
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		CacheBucket& Bucket = *Kv.second;
+		Bucket.GatherReferences(GcCtx);
+	}
+}
+
+uint64_t
+ZenCacheDiskLayer::TotalSize() const
+{
+	uint64_t				TotalSize{};
+	RwLock::SharedLockScope _(m_Lock);
+
+	for (auto& Kv : m_Buckets)
+	{
+		TotalSize += Kv.second->TotalSize();
+	}
+
+	return TotalSize;
+}
+
+ZenCacheDiskLayer::Info
+ZenCacheDiskLayer::GetInfo() const
+{
+	ZenCacheDiskLayer::Info Info = {.Config = {.RootDir = m_RootDir}, .TotalSize = TotalSize()};
+
+	RwLock::SharedLockScope _(m_Lock);
+	Info.BucketNames.reserve(m_Buckets.size());
+	for (auto& Kv : m_Buckets)
+	{
+		Info.BucketNames.push_back(Kv.first);
+		Info.EntryCount += Kv.second->EntryCount();
+	}
+	return Info;
+}
+
+std::optional<ZenCacheDiskLayer::BucketInfo>
+ZenCacheDiskLayer::GetBucketInfo(std::string_view Bucket) const
+{
+	RwLock::SharedLockScope _(m_Lock);
+
+	if (auto It = m_Buckets.find(std::string(Bucket)); It != m_Buckets.end())
+	{
+		return ZenCacheDiskLayer::BucketInfo{.EntryCount = It->second->EntryCount(), .TotalSize = It->second->TotalSize()};
+	}
+	return {};
+}
+
+CacheValueDetails::NamespaceDetails
+ZenCacheDiskLayer::GetValueDetails(const std::string_view BucketFilter, const std::string_view ValueFilter) const
+{
+	RwLock::SharedLockScope				_(m_Lock);
+	CacheValueDetails::NamespaceDetails Details;
+	if (BucketFilter.empty())
+	{
+		Details.Buckets.reserve(BucketFilter.empty() ? m_Buckets.size() : 1);
+		for (auto& Kv : m_Buckets)
+		{
+			Details.Buckets[Kv.first] = Kv.second->GetValueDetails(ValueFilter);
+		}
+	}
+	else if (auto It = m_Buckets.find(std::string(BucketFilter)); It != m_Buckets.end())
+	{
+		Details.Buckets[It->first] = It->second->GetValueDetails(ValueFilter);
+	}
+	return Details;
+}
+
+//////////////////////////// ZenCacheStore
+
+static constexpr std::string_view UE4DDCNamespaceName = "ue4.ddc";
+
+ZenCacheStore::ZenCacheStore(GcManager& Gc, const Configuration& Configuration) : m_Gc(Gc), m_Configuration(Configuration)
+{
+	CreateDirectories(m_Configuration.BasePath);
+
+	DirectoryContent DirContent;
+	GetDirectoryContent(m_Configuration.BasePath, DirectoryContent::IncludeDirsFlag, DirContent);
+
+	std::vector<std::string> Namespaces;
+	for (const std::filesystem::path& DirPath : DirContent.Directories)
+	{
+		std::string DirName = PathToUtf8(DirPath.filename());
+		if (DirName.starts_with(NamespaceDiskPrefix))
+		{
+			Namespaces.push_back(DirName.substr(NamespaceDiskPrefix.length()));
+			continue;
+		}
+	}
+
+	ZEN_INFO("Found {} namespaces in '{}'", Namespaces.size(), m_Configuration.BasePath);
+
+	if (std::find(Namespaces.begin(), Namespaces.end(), UE4DDCNamespaceName) == Namespaces.end())
+	{
+		// default (unspecified) and ue4-ddc namespace points to the same namespace instance
+
+		std::filesystem::path DefaultNamespaceFolder =
+			m_Configuration.BasePath / fmt::format("{}{}", NamespaceDiskPrefix, UE4DDCNamespaceName);
+		CreateDirectories(DefaultNamespaceFolder);
+		Namespaces.push_back(std::string(UE4DDCNamespaceName));
+	}
+
+	for (const std::string& NamespaceName : Namespaces)
+	{
+		m_Namespaces[NamespaceName] =
+			std::make_unique<ZenCacheNamespace>(Gc, m_Configuration.BasePath / fmt::format("{}{}", NamespaceDiskPrefix, NamespaceName));
+	}
+}
+
+ZenCacheStore::~ZenCacheStore()
+{
+	m_Namespaces.clear();
+}
+
+bool
+ZenCacheStore::Get(std::string_view Namespace, std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue)
+{
+	if (ZenCacheNamespace* Store = GetNamespace(Namespace); Store)
+	{
+		return Store->Get(Bucket, HashKey, OutValue);
+	}
+	ZEN_WARN("request for unknown namespace '{}' in ZenCacheStore::Get, bucket '{}', key '{}'", Namespace, Bucket, HashKey.ToHexString());
+
+	return false;
+}
+
+void
+ZenCacheStore::Put(std::string_view Namespace, std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value)
+{
+	if (ZenCacheNamespace* Store = GetNamespace(Namespace); Store)
+	{
+		return Store->Put(Bucket, HashKey, Value);
+	}
+	ZEN_WARN("request for unknown namespace '{}' in ZenCacheStore::Put, bucket '{}', key '{}'", Namespace, Bucket, HashKey.ToHexString());
+}
+
+bool
+ZenCacheStore::DropBucket(std::string_view Namespace, std::string_view Bucket)
+{
+	if (ZenCacheNamespace* Store = GetNamespace(Namespace); Store)
+	{
+		return Store->DropBucket(Bucket);
+	}
+	ZEN_WARN("request for unknown namespace '{}' in ZenCacheStore::DropBucket, bucket '{}'", Namespace, Bucket);
+	return false;
+}
+
+bool
+ZenCacheStore::DropNamespace(std::string_view InNamespace)
+{
+	RwLock::SharedLockScope _(m_NamespacesLock);
+	if (auto It = m_Namespaces.find(std::string(InNamespace)); It != m_Namespaces.end())
+	{
+		ZenCacheNamespace& Namespace = *It->second;
+		m_DroppedNamespaces.push_back(std::move(It->second));
+		m_Namespaces.erase(It);
+		return Namespace.Drop();
+	}
+	ZEN_WARN("request for unknown namespace '{}' in ZenCacheStore::DropNamespace", InNamespace);
+	return false;
+}
+
+void
+ZenCacheStore::Flush()
+{
+	IterateNamespaces([&](std::string_view, ZenCacheNamespace& Store) { Store.Flush(); });
+}
+
+void
+ZenCacheStore::Scrub(ScrubContext& Ctx)
+{
+	IterateNamespaces([&](std::string_view, ZenCacheNamespace& Store) { Store.Scrub(Ctx); });
+}
+
+CacheValueDetails
+ZenCacheStore::GetValueDetails(const std::string_view NamespaceFilter,
+							   const std::string_view BucketFilter,
+							   const std::string_view ValueFilter) const
+{
+	CacheValueDetails Details;
+	if (NamespaceFilter.empty())
+	{
+		IterateNamespaces([&](std::string_view Namespace, ZenCacheNamespace& Store) {
+			Details.Namespaces[std::string(Namespace)] = Store.GetValueDetails(BucketFilter, ValueFilter);
+		});
+	}
+	else if (const ZenCacheNamespace* Store = FindNamespace(NamespaceFilter); Store != nullptr)
+	{
+		Details.Namespaces[std::string(NamespaceFilter)] = Store->GetValueDetails(BucketFilter, ValueFilter);
+	}
+	return Details;
+}
+
+ZenCacheNamespace*
+ZenCacheStore::GetNamespace(std::string_view Namespace)
+{
+	RwLock::SharedLockScope _(m_NamespacesLock);
+	if (auto It = m_Namespaces.find(std::string(Namespace)); It != m_Namespaces.end())
+	{
+		return It->second.get();
+	}
+	if (Namespace == DefaultNamespace)
+	{
+		if (auto It = m_Namespaces.find(std::string(UE4DDCNamespaceName)); It != m_Namespaces.end())
+		{
+			return It->second.get();
+		}
+	}
+	_.ReleaseNow();
+
+	if (!m_Configuration.AllowAutomaticCreationOfNamespaces)
+	{
+		return nullptr;
+	}
+
+	RwLock::ExclusiveLockScope __(m_NamespacesLock);
+	if (auto It = m_Namespaces.find(std::string(Namespace)); It != m_Namespaces.end())
+	{
+		return It->second.get();
+	}
+
+	auto NewNamespace = m_Namespaces.insert_or_assign(
+		std::string(Namespace),
+		std::make_unique<ZenCacheNamespace>(m_Gc, m_Configuration.BasePath / fmt::format("{}{}", NamespaceDiskPrefix, Namespace)));
+	return NewNamespace.first->second.get();
+}
+
+const ZenCacheNamespace*
+ZenCacheStore::FindNamespace(std::string_view Namespace) const
+{
+	RwLock::SharedLockScope _(m_NamespacesLock);
+	if (auto It = m_Namespaces.find(std::string(Namespace)); It != m_Namespaces.end())
+	{
+		return It->second.get();
+	}
+	if (Namespace == DefaultNamespace)
+	{
+		if (auto It = m_Namespaces.find(std::string(UE4DDCNamespaceName)); It != m_Namespaces.end())
+		{
+			return It->second.get();
+		}
+	}
+	return nullptr;
+}
+
+void
+ZenCacheStore::IterateNamespaces(const std::function<void(std::string_view Namespace, ZenCacheNamespace& Store)>& Callback) const
+{
+	std::vector<std::pair<std::string, ZenCacheNamespace&>> Namespaces;
+	{
+		RwLock::SharedLockScope _(m_NamespacesLock);
+		Namespaces.reserve(m_Namespaces.size());
+		for (const auto& Entry : m_Namespaces)
+		{
+			if (Entry.first == DefaultNamespace)
+			{
+				continue;
+			}
+			Namespaces.push_back({Entry.first, *Entry.second});
+		}
+	}
+	for (auto& Entry : Namespaces)
+	{
+		Callback(Entry.first, Entry.second);
+	}
+}
+
+GcStorageSize
+ZenCacheStore::StorageSize() const
+{
+	GcStorageSize Size;
+	IterateNamespaces([&](std::string_view, ZenCacheNamespace& Store) {
+		GcStorageSize StoreSize = Store.StorageSize();
+		Size.MemorySize += StoreSize.MemorySize;
+		Size.DiskSize += StoreSize.DiskSize;
+	});
+	return Size;
+}
+
+ZenCacheStore::Info
+ZenCacheStore::GetInfo() const
+{
+	ZenCacheStore::Info Info = {.Config = m_Configuration, .StorageSize = StorageSize()};
+
+	IterateNamespaces([&Info](std::string_view NamespaceName, ZenCacheNamespace& Namespace) {
+		Info.NamespaceNames.push_back(std::string(NamespaceName));
+		ZenCacheNamespace::Info NamespaceInfo = Namespace.GetInfo();
+		Info.DiskEntryCount += NamespaceInfo.DiskLayerInfo.EntryCount;
+		Info.MemoryEntryCount += NamespaceInfo.MemoryLayerInfo.EntryCount;
+	});
+
+	return Info;
+}
+
+std::optional<ZenCacheNamespace::Info>
+ZenCacheStore::GetNamespaceInfo(std::string_view NamespaceName)
+{
+	if (const ZenCacheNamespace* Namespace = FindNamespace(NamespaceName); Namespace)
+	{
+		return Namespace->GetInfo();
+	}
+	return {};
+}
+
+std::optional<ZenCacheNamespace::BucketInfo>
+ZenCacheStore::GetBucketInfo(std::string_view NamespaceName, std::string_view BucketName)
+{
+	if (const ZenCacheNamespace* Namespace = FindNamespace(NamespaceName); Namespace)
+	{
+		return Namespace->GetBucketInfo(BucketName);
+	}
+	return {};
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+#if ZEN_WITH_TESTS
+
+using namespace std::literals;
+
+namespace testutils {
+	IoHash CreateKey(size_t KeyValue) { return IoHash::HashBuffer(&KeyValue, sizeof(size_t)); }
+
+	IoBuffer CreateBinaryCacheValue(uint64_t Size)
+	{
+		static std::random_device rd;
+		static std::mt19937		  g(rd());
+
+		std::vector<uint8_t> Values;
+		Values.resize(Size);
+		for (size_t Idx = 0; Idx < Size; ++Idx)
+		{
+			Values[Idx] = static_cast<uint8_t>(Idx);
+		}
+		std::shuffle(Values.begin(), Values.end(), g);
+
+		IoBuffer Buf(IoBuffer::Clone, Values.data(), Values.size());
+		Buf.SetContentType(ZenContentType::kBinary);
+		return Buf;
+	};
+
+}  // namespace testutils
+
+TEST_CASE("z$.store")
+{
+	ScopedTemporaryDirectory TempDir;
+
+	GcManager Gc;
+
+	ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+
+	const int kIterationCount = 100;
+
+	for (int i = 0; i < kIterationCount; ++i)
+	{
+		const IoHash Key = IoHash::HashBuffer(&i, sizeof i);
+
+		CbObjectWriter Cbo;
+		Cbo << "hey" << i;
+		CbObject Obj = Cbo.Save();
+
+		ZenCacheValue Value;
+		Value.Value = Obj.GetBuffer().AsIoBuffer();
+		Value.Value.SetContentType(ZenContentType::kCbObject);
+
+		Zcs.Put("test_bucket"sv, Key, Value);
+	}
+
+	for (int i = 0; i < kIterationCount; ++i)
+	{
+		const IoHash Key = IoHash::HashBuffer(&i, sizeof i);
+
+		ZenCacheValue Value;
+		Zcs.Get("test_bucket"sv, Key, /* out */ Value);
+
+		REQUIRE(Value.Value);
+		CHECK(Value.Value.GetContentType() == ZenContentType::kCbObject);
+		CHECK_EQ(ValidateCompactBinary(Value.Value, CbValidateMode::All), CbValidateError::None);
+		CbObject Obj = LoadCompactBinaryObject(Value.Value);
+		CHECK_EQ(Obj["hey"].AsInt32(), i);
+	}
+}
+
+TEST_CASE("z$.size")
+{
+	const auto CreateCacheValue = [](size_t Size) -> CbObject {
+		std::vector<uint8_t> Buf;
+		Buf.resize(Size);
+
+		CbObjectWriter Writer;
+		Writer.AddBinary("Binary"sv, Buf.data(), Buf.size());
+		return Writer.Save();
+	};
+
+	SUBCASE("mem/disklayer")
+	{
+		const size_t			 Count = 16;
+		ScopedTemporaryDirectory TempDir;
+
+		GcStorageSize CacheSize;
+
+		{
+			GcManager		  Gc;
+			ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+
+			CbObject CacheValue = CreateCacheValue(Zcs.DiskLayerThreshold() - 256);
+
+			IoBuffer Buffer = CacheValue.GetBuffer().AsIoBuffer();
+			Buffer.SetContentType(ZenContentType::kCbObject);
+
+			for (size_t Key = 0; Key < Count; ++Key)
+			{
+				const size_t Bucket = Key % 4;
+				Zcs.Put(fmt::format("test_bucket-{}", Bucket), IoHash::HashBuffer(&Key, sizeof(uint32_t)), ZenCacheValue{.Value = Buffer});
+			}
+
+			CacheSize = Zcs.StorageSize();
+			CHECK_LE(CacheValue.GetSize() * Count, CacheSize.DiskSize);
+			CHECK_LE(CacheValue.GetSize() * Count, CacheSize.MemorySize);
+		}
+
+		{
+			GcManager		  Gc;
+			ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+
+			const GcStorageSize SerializedSize = Zcs.StorageSize();
+			CHECK_EQ(SerializedSize.MemorySize, 0);
+			CHECK_LE(SerializedSize.DiskSize, CacheSize.DiskSize);
+
+			for (size_t Bucket = 0; Bucket < 4; ++Bucket)
+			{
+				Zcs.DropBucket(fmt::format("test_bucket-{}", Bucket));
+			}
+			CHECK_EQ(0, Zcs.StorageSize().DiskSize);
+		}
+	}
+
+	SUBCASE("disklayer")
+	{
+		const size_t			 Count = 16;
+		ScopedTemporaryDirectory TempDir;
+
+		GcStorageSize CacheSize;
+
+		{
+			GcManager		  Gc;
+			ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+
+			CbObject CacheValue = CreateCacheValue(Zcs.DiskLayerThreshold() + 64);
+
+			IoBuffer Buffer = CacheValue.GetBuffer().AsIoBuffer();
+			Buffer.SetContentType(ZenContentType::kCbObject);
+
+			for (size_t Key = 0; Key < Count; ++Key)
+			{
+				const size_t Bucket = Key % 4;
+				Zcs.Put(fmt::format("test_bucket-{}", Bucket), IoHash::HashBuffer(&Key, sizeof(uint32_t)), {.Value = Buffer});
+			}
+
+			CacheSize = Zcs.StorageSize();
+			CHECK_LE(CacheValue.GetSize() * Count, CacheSize.DiskSize);
+			CHECK_EQ(0, CacheSize.MemorySize);
+		}
+
+		{
+			GcManager		  Gc;
+			ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+
+			const GcStorageSize SerializedSize = Zcs.StorageSize();
+			CHECK_EQ(SerializedSize.MemorySize, 0);
+			CHECK_LE(SerializedSize.DiskSize, CacheSize.DiskSize);
+
+			for (size_t Bucket = 0; Bucket < 4; ++Bucket)
+			{
+				Zcs.DropBucket(fmt::format("test_bucket-{}", Bucket));
+			}
+			CHECK_EQ(0, Zcs.StorageSize().DiskSize);
+		}
+	}
+}
+
+TEST_CASE("z$.gc")
+{
+	using namespace testutils;
+
+	SUBCASE("gather references does NOT add references for expired cache entries")
+	{
+		ScopedTemporaryDirectory TempDir;
+		std::vector<IoHash>		 Cids{CreateKey(1), CreateKey(2), CreateKey(3)};
+
+		const auto CollectAndFilter = [](GcManager&				 Gc,
+										 GcClock::TimePoint		 Time,
+										 GcClock::Duration		 MaxDuration,
+										 std::span<const IoHash> Cids,
+										 std::vector<IoHash>&	 OutKeep) {
+			GcContext GcCtx(Time - MaxDuration);
+			Gc.CollectGarbage(GcCtx);
+			OutKeep.clear();
+			GcCtx.FilterCids(Cids, [&OutKeep](const IoHash& Hash) { OutKeep.push_back(Hash); });
+		};
+
+		{
+			GcManager		  Gc;
+			ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+			const auto		  Bucket = "teardrinker"sv;
+
+			// Create a cache record
+			const IoHash   Key = CreateKey(42);
+			CbObjectWriter Record;
+			Record << "Key"sv
+				   << "SomeRecord"sv;
+
+			for (size_t Idx = 0; auto& Cid : Cids)
+			{
+				Record.AddBinaryAttachment(fmt::format("attachment-{}", Idx++), Cid);
+			}
+
+			IoBuffer Buffer = Record.Save().GetBuffer().AsIoBuffer();
+			Buffer.SetContentType(ZenContentType::kCbObject);
+
+			Zcs.Put(Bucket, Key, {.Value = Buffer});
+
+			std::vector<IoHash> Keep;
+
+			// Collect garbage with 1 hour max cache duration
+			{
+				CollectAndFilter(Gc, GcClock::Now(), std::chrono::hours(1), Cids, Keep);
+				CHECK_EQ(Cids.size(), Keep.size());
+			}
+
+			// Move forward in time
+			{
+				CollectAndFilter(Gc, GcClock::Now() + std::chrono::hours(2), std::chrono::hours(1), Cids, Keep);
+				CHECK_EQ(0, Keep.size());
+			}
+		}
+
+		// Expect timestamps to be serialized
+		{
+			GcManager			Gc;
+			ZenCacheNamespace	Zcs(Gc, TempDir.Path() / "cache");
+			std::vector<IoHash> Keep;
+
+			// Collect garbage with 1 hour max cache duration
+			{
+				CollectAndFilter(Gc, GcClock::Now(), std::chrono::hours(1), Cids, Keep);
+				CHECK_EQ(3, Keep.size());
+			}
+
+			// Move forward in time
+			{
+				CollectAndFilter(Gc, GcClock::Now() + std::chrono::hours(2), std::chrono::hours(1), Cids, Keep);
+				CHECK_EQ(0, Keep.size());
+			}
+		}
+	}
+
+	SUBCASE("gc removes standalone values")
+	{
+		ScopedTemporaryDirectory TempDir;
+		GcManager				 Gc;
+		ZenCacheNamespace		 Zcs(Gc, TempDir.Path() / "cache");
+		const auto				 Bucket		 = "fortysixandtwo"sv;
+		const GcClock::TimePoint CurrentTime = GcClock::Now();
+
+		std::vector<IoHash> Keys{CreateKey(1), CreateKey(2), CreateKey(3)};
+
+		for (const auto& Key : Keys)
+		{
+			IoBuffer Value = testutils::CreateBinaryCacheValue(128 << 10);
+			Zcs.Put(Bucket, Key, {.Value = Value});
+		}
+
+		{
+			GcContext GcCtx(CurrentTime - std::chrono::hours(46));
+
+			Gc.CollectGarbage(GcCtx);
+
+			for (const auto& Key : Keys)
+			{
+				ZenCacheValue CacheValue;
+				const bool	  Exists = Zcs.Get(Bucket, Key, CacheValue);
+				CHECK(Exists);
+			}
+		}
+
+		// Move forward in time and collect again
+		{
+			GcContext GcCtx(CurrentTime + std::chrono::minutes(2));
+			Gc.CollectGarbage(GcCtx);
+
+			for (const auto& Key : Keys)
+			{
+				ZenCacheValue CacheValue;
+				const bool	  Exists = Zcs.Get(Bucket, Key, CacheValue);
+				CHECK(!Exists);
+			}
+
+			CHECK_EQ(0, Zcs.StorageSize().DiskSize);
+		}
+	}
+
+	SUBCASE("gc removes small objects")
+	{
+		ScopedTemporaryDirectory TempDir;
+		GcManager				 Gc;
+		ZenCacheNamespace		 Zcs(Gc, TempDir.Path() / "cache");
+		const auto				 Bucket = "rightintwo"sv;
+
+		std::vector<IoHash> Keys{CreateKey(1), CreateKey(2), CreateKey(3)};
+
+		for (const auto& Key : Keys)
+		{
+			IoBuffer Value = testutils::CreateBinaryCacheValue(128);
+			Zcs.Put(Bucket, Key, {.Value = Value});
+		}
+
+		{
+			GcContext GcCtx(GcClock::Now() - std::chrono::hours(2));
+			GcCtx.CollectSmallObjects(true);
+
+			Gc.CollectGarbage(GcCtx);
+
+			for (const auto& Key : Keys)
+			{
+				ZenCacheValue CacheValue;
+				const bool	  Exists = Zcs.Get(Bucket, Key, CacheValue);
+				CHECK(Exists);
+			}
+		}
+
+		// Move forward in time and collect again
+		{
+			GcContext GcCtx(GcClock::Now() + std::chrono::minutes(2));
+			GcCtx.CollectSmallObjects(true);
+
+			Zcs.Flush();
+			Gc.CollectGarbage(GcCtx);
+
+			for (const auto& Key : Keys)
+			{
+				ZenCacheValue CacheValue;
+				const bool	  Exists = Zcs.Get(Bucket, Key, CacheValue);
+				CHECK(!Exists);
+			}
+
+			CHECK_EQ(0, Zcs.StorageSize().DiskSize);
+		}
+	}
+}
+
+TEST_CASE("z$.threadedinsert")	// * doctest::skip(true))
+{
+	//	for (uint32_t i = 0; i < 100; ++i)
+	{
+		ScopedTemporaryDirectory TempDir;
+
+		const uint64_t kChunkSize  = 1048;
+		const int32_t  kChunkCount = 8192;
+
+		struct Chunk
+		{
+			std::string Bucket;
+			IoBuffer	Buffer;
+		};
+		std::unordered_map<IoHash, Chunk, IoHash::Hasher> Chunks;
+		Chunks.reserve(kChunkCount);
+
+		const std::string Bucket1 = "rightinone";
+		const std::string Bucket2 = "rightintwo";
+
+		for (int32_t Idx = 0; Idx < kChunkCount; ++Idx)
+		{
+			while (true)
+			{
+				IoBuffer Chunk = testutils::CreateBinaryCacheValue(kChunkSize);
+				IoHash	 Hash  = HashBuffer(Chunk);
+				if (Chunks.contains(Hash))
+				{
+					continue;
+				}
+				Chunks[Hash] = {.Bucket = Bucket1, .Buffer = Chunk};
+				break;
+			}
+			while (true)
+			{
+				IoBuffer Chunk = testutils::CreateBinaryCacheValue(kChunkSize);
+				IoHash	 Hash  = HashBuffer(Chunk);
+				if (Chunks.contains(Hash))
+				{
+					continue;
+				}
+				Chunks[Hash] = {.Bucket = Bucket2, .Buffer = Chunk};
+				break;
+			}
+		}
+
+		CreateDirectories(TempDir.Path());
+
+		WorkerThreadPool  ThreadPool(4);
+		GcManager		  Gc;
+		ZenCacheNamespace Zcs(Gc, TempDir.Path());
+
+		{
+			std::atomic<size_t> WorkCompleted = 0;
+			for (const auto& Chunk : Chunks)
+			{
+				ThreadPool.ScheduleWork([&Zcs, &WorkCompleted, &Chunk]() {
+					Zcs.Put(Chunk.second.Bucket, Chunk.first, {.Value = Chunk.second.Buffer});
+					WorkCompleted.fetch_add(1);
+				});
+			}
+			while (WorkCompleted < Chunks.size())
+			{
+				Sleep(1);
+			}
+		}
+
+		const uint64_t TotalSize = Zcs.StorageSize().DiskSize;
+		CHECK_LE(kChunkSize * Chunks.size(), TotalSize);
+
+		{
+			std::atomic<size_t> WorkCompleted = 0;
+			for (const auto& Chunk : Chunks)
+			{
+				ThreadPool.ScheduleWork([&Zcs, &WorkCompleted, &Chunk]() {
+					std::string	  Bucket	= Chunk.second.Bucket;
+					IoHash		  ChunkHash = Chunk.first;
+					ZenCacheValue CacheValue;
+
+					CHECK(Zcs.Get(Bucket, ChunkHash, CacheValue));
+					IoHash Hash = IoHash::HashBuffer(CacheValue.Value);
+					CHECK(ChunkHash == Hash);
+					WorkCompleted.fetch_add(1);
+				});
+			}
+			while (WorkCompleted < Chunks.size())
+			{
+				Sleep(1);
+			}
+		}
+		std::unordered_map<IoHash, std::string, IoHash::Hasher> GcChunkHashes;
+		GcChunkHashes.reserve(Chunks.size());
+		for (const auto& Chunk : Chunks)
+		{
+			GcChunkHashes[Chunk.first] = Chunk.second.Bucket;
+		}
+		{
+			std::unordered_map<IoHash, Chunk, IoHash::Hasher> NewChunks;
+
+			for (int32_t Idx = 0; Idx < kChunkCount; ++Idx)
+			{
+				{
+					IoBuffer Chunk	= testutils::CreateBinaryCacheValue(kChunkSize);
+					IoHash	 Hash	= HashBuffer(Chunk);
+					NewChunks[Hash] = {.Bucket = Bucket1, .Buffer = Chunk};
+				}
+				{
+					IoBuffer Chunk	= testutils::CreateBinaryCacheValue(kChunkSize);
+					IoHash	 Hash	= HashBuffer(Chunk);
+					NewChunks[Hash] = {.Bucket = Bucket2, .Buffer = Chunk};
+				}
+			}
+
+			std::atomic<size_t>	 WorkCompleted	 = 0;
+			std::atomic_uint32_t AddedChunkCount = 0;
+			for (const auto& Chunk : NewChunks)
+			{
+				ThreadPool.ScheduleWork([&Zcs, &WorkCompleted, Chunk, &AddedChunkCount]() {
+					Zcs.Put(Chunk.second.Bucket, Chunk.first, {.Value = Chunk.second.Buffer});
+					AddedChunkCount.fetch_add(1);
+					WorkCompleted.fetch_add(1);
+				});
+			}
+
+			for (const auto& Chunk : Chunks)
+			{
+				ThreadPool.ScheduleWork([&Zcs, &WorkCompleted, Chunk]() {
+					ZenCacheValue CacheValue;
+					if (Zcs.Get(Chunk.second.Bucket, Chunk.first, CacheValue))
+					{
+						CHECK(Chunk.first == IoHash::HashBuffer(CacheValue.Value));
+					}
+					WorkCompleted.fetch_add(1);
+				});
+			}
+			while (AddedChunkCount.load() < NewChunks.size())
+			{
+				// Need to be careful since we might GC blocks we don't know outside of RwLock::ExclusiveLockScope
+				for (const auto& Chunk : NewChunks)
+				{
+					ZenCacheValue CacheValue;
+					if (Zcs.Get(Chunk.second.Bucket, Chunk.first, CacheValue))
+					{
+						GcChunkHashes[Chunk.first] = Chunk.second.Bucket;
+					}
+				}
+				std::vector<IoHash> KeepHashes;
+				KeepHashes.reserve(GcChunkHashes.size());
+				for (const auto& Entry : GcChunkHashes)
+				{
+					KeepHashes.push_back(Entry.first);
+				}
+				size_t C = 0;
+				while (C < KeepHashes.size())
+				{
+					if (C % 155 == 0)
+					{
+						if (C < KeepHashes.size() - 1)
+						{
+							KeepHashes[C] = KeepHashes[KeepHashes.size() - 1];
+							KeepHashes.pop_back();
+						}
+						if (C + 3 < KeepHashes.size() - 1)
+						{
+							KeepHashes[C + 3] = KeepHashes[KeepHashes.size() - 1];
+							KeepHashes.pop_back();
+						}
+					}
+					C++;
+				}
+
+				GcContext GcCtx(GcClock::Now() - std::chrono::hours(24));
+				GcCtx.CollectSmallObjects(true);
+				GcCtx.AddRetainedCids(KeepHashes);
+				Zcs.CollectGarbage(GcCtx);
+				const HashKeySet& Deleted = GcCtx.DeletedCids();
+				Deleted.IterateHashes([&GcChunkHashes](const IoHash& ChunkHash) { GcChunkHashes.erase(ChunkHash); });
+			}
+
+			while (WorkCompleted < NewChunks.size() + Chunks.size())
+			{
+				Sleep(1);
+			}
+
+			{
+				// Need to be careful since we might GC blocks we don't know outside of RwLock::ExclusiveLockScope
+				for (const auto& Chunk : NewChunks)
+				{
+					ZenCacheValue CacheValue;
+					if (Zcs.Get(Chunk.second.Bucket, Chunk.first, CacheValue))
+					{
+						GcChunkHashes[Chunk.first] = Chunk.second.Bucket;
+					}
+				}
+				std::vector<IoHash> KeepHashes;
+				KeepHashes.reserve(GcChunkHashes.size());
+				for (const auto& Entry : GcChunkHashes)
+				{
+					KeepHashes.push_back(Entry.first);
+				}
+				size_t C = 0;
+				while (C < KeepHashes.size())
+				{
+					if (C % 155 == 0)
+					{
+						if (C < KeepHashes.size() - 1)
+						{
+							KeepHashes[C] = KeepHashes[KeepHashes.size() - 1];
+							KeepHashes.pop_back();
+						}
+						if (C + 3 < KeepHashes.size() - 1)
+						{
+							KeepHashes[C + 3] = KeepHashes[KeepHashes.size() - 1];
+							KeepHashes.pop_back();
+						}
+					}
+					C++;
+				}
+
+				GcContext GcCtx(GcClock::Now() - std::chrono::hours(24));
+				GcCtx.CollectSmallObjects(true);
+				GcCtx.AddRetainedCids(KeepHashes);
+				Zcs.CollectGarbage(GcCtx);
+				const HashKeySet& Deleted = GcCtx.DeletedCids();
+				Deleted.IterateHashes([&GcChunkHashes](const IoHash& ChunkHash) { GcChunkHashes.erase(ChunkHash); });
+			}
+		}
+		{
+			std::atomic<size_t> WorkCompleted = 0;
+			for (const auto& Chunk : GcChunkHashes)
+			{
+				ThreadPool.ScheduleWork([&Zcs, &WorkCompleted, Chunk]() {
+					ZenCacheValue CacheValue;
+					CHECK(Zcs.Get(Chunk.second, Chunk.first, CacheValue));
+					CHECK(Chunk.first == IoHash::HashBuffer(CacheValue.Value));
+					WorkCompleted.fetch_add(1);
+				});
+			}
+			while (WorkCompleted < GcChunkHashes.size())
+			{
+				Sleep(1);
+			}
+		}
+	}
+}
+
+TEST_CASE("z$.namespaces")
+{
+	using namespace testutils;
+
+	const auto CreateCacheValue = [](size_t Size) -> CbObject {
+		std::vector<uint8_t> Buf;
+		Buf.resize(Size);
+
+		CbObjectWriter Writer;
+		Writer.AddBinary("Binary"sv, Buf.data(), Buf.size());
+		return Writer.Save();
+	};
+
+	ScopedTemporaryDirectory TempDir;
+	CreateDirectories(TempDir.Path());
+
+	IoHash Key1;
+	IoHash Key2;
+	{
+		GcManager	  Gc;
+		ZenCacheStore Zcs(Gc, {.BasePath = TempDir.Path() / "cache", .AllowAutomaticCreationOfNamespaces = false});
+		const auto	  Bucket		  = "teardrinker"sv;
+		const auto	  CustomNamespace = "mynamespace"sv;
+
+		// Create a cache record
+		Key1				= CreateKey(42);
+		CbObject CacheValue = CreateCacheValue(4096);
+
+		IoBuffer Buffer = CacheValue.GetBuffer().AsIoBuffer();
+		Buffer.SetContentType(ZenContentType::kCbObject);
+
+		ZenCacheValue PutValue = {.Value = Buffer};
+		Zcs.Put(ZenCacheStore::DefaultNamespace, Bucket, Key1, PutValue);
+
+		ZenCacheValue GetValue;
+		CHECK(Zcs.Get(ZenCacheStore::DefaultNamespace, Bucket, Key1, GetValue));
+		CHECK(!Zcs.Get(CustomNamespace, Bucket, Key1, GetValue));
+
+		// This should just be dropped as we don't allow creating of namespaces on the fly
+		Zcs.Put(CustomNamespace, Bucket, Key1, PutValue);
+		CHECK(!Zcs.Get(CustomNamespace, Bucket, Key1, GetValue));
+	}
+
+	{
+		GcManager	  Gc;
+		ZenCacheStore Zcs(Gc, {.BasePath = TempDir.Path() / "cache", .AllowAutomaticCreationOfNamespaces = true});
+		const auto	  Bucket		  = "teardrinker"sv;
+		const auto	  CustomNamespace = "mynamespace"sv;
+
+		Key2				 = CreateKey(43);
+		CbObject CacheValue2 = CreateCacheValue(4096);
+
+		IoBuffer Buffer2 = CacheValue2.GetBuffer().AsIoBuffer();
+		Buffer2.SetContentType(ZenContentType::kCbObject);
+		ZenCacheValue PutValue2 = {.Value = Buffer2};
+		Zcs.Put(CustomNamespace, Bucket, Key2, PutValue2);
+
+		ZenCacheValue GetValue;
+		CHECK(!Zcs.Get(ZenCacheStore::DefaultNamespace, Bucket, Key2, GetValue));
+		CHECK(Zcs.Get(ZenCacheStore::DefaultNamespace, Bucket, Key1, GetValue));
+		CHECK(!Zcs.Get(CustomNamespace, Bucket, Key1, GetValue));
+		CHECK(Zcs.Get(CustomNamespace, Bucket, Key2, GetValue));
+	}
+}
+
+TEST_CASE("z$.drop.bucket")
+{
+	using namespace testutils;
+
+	const auto CreateCacheValue = [](size_t Size) -> CbObject {
+		std::vector<uint8_t> Buf;
+		Buf.resize(Size);
+
+		CbObjectWriter Writer;
+		Writer.AddBinary("Binary"sv, Buf.data(), Buf.size());
+		return Writer.Save();
+	};
+
+	ScopedTemporaryDirectory TempDir;
+	CreateDirectories(TempDir.Path());
+
+	IoHash Key1;
+	IoHash Key2;
+
+	auto PutValue =
+		[&CreateCacheValue](ZenCacheStore& Zcs, std::string_view Namespace, std::string_view Bucket, size_t KeyIndex, size_t Size) {
+			// Create a cache record
+			IoHash	 Key		= CreateKey(KeyIndex);
+			CbObject CacheValue = CreateCacheValue(Size);
+
+			IoBuffer Buffer = CacheValue.GetBuffer().AsIoBuffer();
+			Buffer.SetContentType(ZenContentType::kCbObject);
+
+			ZenCacheValue PutValue = {.Value = Buffer};
+			Zcs.Put(Namespace, Bucket, Key, PutValue);
+			return Key;
+		};
+	auto GetValue = [](ZenCacheStore& Zcs, std::string_view Namespace, std::string_view Bucket, const IoHash& Key) {
+		ZenCacheValue GetValue;
+		Zcs.Get(Namespace, Bucket, Key, GetValue);
+		return GetValue;
+	};
+	WorkerThreadPool Workers(1);
+	{
+		GcManager	  Gc;
+		ZenCacheStore Zcs(Gc, {.BasePath = TempDir.Path() / "cache", .AllowAutomaticCreationOfNamespaces = true});
+		const auto	  Bucket	= "teardrinker"sv;
+		const auto	  Namespace = "mynamespace"sv;
+
+		Key1 = PutValue(Zcs, Namespace, Bucket, 42, 4096);
+		Key2 = PutValue(Zcs, Namespace, Bucket, 43, 2048);
+
+		ZenCacheValue Value1 = GetValue(Zcs, Namespace, Bucket, Key1);
+		CHECK(Value1.Value);
+
+		std::atomic_bool WorkComplete = false;
+		Workers.ScheduleWork([&]() {
+			zen::Sleep(100);
+			Value1.Value = IoBuffer{};
+			WorkComplete = true;
+		});
+		// On Windows, DropBucket() will be blocked as long as we hold a reference to a buffer in the bucket
+		// Our DropBucket execution blocks any incoming request from completing until we are done with the drop
+		CHECK(Zcs.DropBucket(Namespace, Bucket));
+		while (!WorkComplete)
+		{
+			zen::Sleep(1);
+		}
+
+		// Entire bucket should be dropped, but doing a request should will re-create the namespace but it must still be empty
+		Value1 = GetValue(Zcs, Namespace, Bucket, Key1);
+		CHECK(!Value1.Value);
+		ZenCacheValue Value2 = GetValue(Zcs, Namespace, Bucket, Key2);
+		CHECK(!Value2.Value);
+	}
+}
+
+TEST_CASE("z$.drop.namespace")
+{
+	using namespace testutils;
+
+	const auto CreateCacheValue = [](size_t Size) -> CbObject {
+		std::vector<uint8_t> Buf;
+		Buf.resize(Size);
+
+		CbObjectWriter Writer;
+		Writer.AddBinary("Binary"sv, Buf.data(), Buf.size());
+		return Writer.Save();
+	};
+
+	ScopedTemporaryDirectory TempDir;
+	CreateDirectories(TempDir.Path());
+
+	auto PutValue =
+		[&CreateCacheValue](ZenCacheStore& Zcs, std::string_view Namespace, std::string_view Bucket, size_t KeyIndex, size_t Size) {
+			// Create a cache record
+			IoHash	 Key		= CreateKey(KeyIndex);
+			CbObject CacheValue = CreateCacheValue(Size);
+
+			IoBuffer Buffer = CacheValue.GetBuffer().AsIoBuffer();
+			Buffer.SetContentType(ZenContentType::kCbObject);
+
+			ZenCacheValue PutValue = {.Value = Buffer};
+			Zcs.Put(Namespace, Bucket, Key, PutValue);
+			return Key;
+		};
+	auto GetValue = [](ZenCacheStore& Zcs, std::string_view Namespace, std::string_view Bucket, const IoHash& Key) {
+		ZenCacheValue GetValue;
+		Zcs.Get(Namespace, Bucket, Key, GetValue);
+		return GetValue;
+	};
+	WorkerThreadPool Workers(1);
+	{
+		GcManager	  Gc;
+		ZenCacheStore Zcs(Gc, {.BasePath = TempDir.Path() / "cache", .AllowAutomaticCreationOfNamespaces = true});
+		const auto	  Bucket1	 = "teardrinker1"sv;
+		const auto	  Bucket2	 = "teardrinker2"sv;
+		const auto	  Namespace1 = "mynamespace1"sv;
+		const auto	  Namespace2 = "mynamespace2"sv;
+
+		IoHash Key1 = PutValue(Zcs, Namespace1, Bucket1, 42, 4096);
+		IoHash Key2 = PutValue(Zcs, Namespace1, Bucket2, 43, 2048);
+		IoHash Key3 = PutValue(Zcs, Namespace2, Bucket1, 44, 4096);
+		IoHash Key4 = PutValue(Zcs, Namespace2, Bucket2, 45, 2048);
+
+		ZenCacheValue Value1 = GetValue(Zcs, Namespace1, Bucket1, Key1);
+		CHECK(Value1.Value);
+		ZenCacheValue Value2 = GetValue(Zcs, Namespace1, Bucket2, Key2);
+		CHECK(Value2.Value);
+		ZenCacheValue Value3 = GetValue(Zcs, Namespace2, Bucket1, Key3);
+		CHECK(Value3.Value);
+		ZenCacheValue Value4 = GetValue(Zcs, Namespace2, Bucket2, Key4);
+		CHECK(Value4.Value);
+
+		std::atomic_bool WorkComplete = false;
+		Workers.ScheduleWork([&]() {
+			zen::Sleep(100);
+			Value1.Value = IoBuffer{};
+			Value2.Value = IoBuffer{};
+			Value3.Value = IoBuffer{};
+			Value4.Value = IoBuffer{};
+			WorkComplete = true;
+		});
+		// On Windows, DropBucket() will be blocked as long as we hold a reference to a buffer in the bucket
+		// Our DropBucket execution blocks any incoming request from completing until we are done with the drop
+		CHECK(Zcs.DropNamespace(Namespace1));
+		while (!WorkComplete)
+		{
+			zen::Sleep(1);
+		}
+
+		// Entire namespace should be dropped, but doing a request should will re-create the namespace but it must still be empty
+		Value1 = GetValue(Zcs, Namespace1, Bucket1, Key1);
+		CHECK(!Value1.Value);
+		Value2 = GetValue(Zcs, Namespace1, Bucket2, Key2);
+		CHECK(!Value2.Value);
+		Value3 = GetValue(Zcs, Namespace2, Bucket1, Key3);
+		CHECK(Value3.Value);
+		Value4 = GetValue(Zcs, Namespace2, Bucket2, Key4);
+		CHECK(Value4.Value);
+	}
+}
+
+TEST_CASE("z$.blocked.disklayer.put")
+{
+	ScopedTemporaryDirectory TempDir;
+
+	GcStorageSize CacheSize;
+
+	const auto CreateCacheValue = [](size_t Size) -> CbObject {
+		std::vector<uint8_t> Buf;
+		Buf.resize(Size, Size & 0xff);
+
+		CbObjectWriter Writer;
+		Writer.AddBinary("Binary"sv, Buf.data(), Buf.size());
+		return Writer.Save();
+	};
+
+	GcManager		  Gc;
+	ZenCacheNamespace Zcs(Gc, TempDir.Path() / "cache");
+
+	CbObject CacheValue = CreateCacheValue(64 * 1024 + 64);
+
+	IoBuffer Buffer = CacheValue.GetBuffer().AsIoBuffer();
+	Buffer.SetContentType(ZenContentType::kCbObject);
+
+	size_t Key	   = Buffer.Size();
+	IoHash HashKey = IoHash::HashBuffer(&Key, sizeof(uint32_t));
+	Zcs.Put("test_bucket", HashKey, {.Value = Buffer});
+
+	ZenCacheValue BufferGet;
+	CHECK(Zcs.Get("test_bucket", HashKey, BufferGet));
+
+	CbObject CacheValue2 = CreateCacheValue(64 * 1024 + 64 + 1);
+	IoBuffer Buffer2	 = CacheValue2.GetBuffer().AsIoBuffer();
+	Buffer2.SetContentType(ZenContentType::kCbObject);
+
+	// We should be able to overwrite even if the file is open for read
+	Zcs.Put("test_bucket", HashKey, {.Value = Buffer2});
+
+	MemoryView OldView = BufferGet.Value.GetView();
+
+	ZenCacheValue BufferGet2;
+	CHECK(Zcs.Get("test_bucket", HashKey, BufferGet2));
+	MemoryView NewView = BufferGet2.Value.GetView();
+
+	// Make sure file openend for read before we wrote it still have old data
+	CHECK(OldView.GetSize() == Buffer.GetSize());
+	CHECK(memcmp(OldView.GetData(), Buffer.GetData(), OldView.GetSize()) == 0);
+
+	// Make sure we get the new data when reading after we write new data
+	CHECK(NewView.GetSize() == Buffer2.GetSize());
+	CHECK(memcmp(NewView.GetData(), Buffer2.GetData(), NewView.GetSize()) == 0);
+}
+
+TEST_CASE("z$.scrub")
+{
+	ScopedTemporaryDirectory TempDir;
+
+	using namespace testutils;
+
+	struct CacheRecord
+	{
+		IoBuffer					  Record;
+		std::vector<CompressedBuffer> Attachments;
+	};
+
+	auto CreateCacheRecord = [](bool Structured, std::string_view Bucket, const IoHash& Key, const std::vector<size_t>& AttachmentSizes) {
+		CacheRecord Result;
+		if (Structured)
+		{
+			Result.Attachments.resize(AttachmentSizes.size());
+			CbObjectWriter Record;
+			Record.BeginObject("Key"sv);
+			{
+				Record << "Bucket"sv << Bucket;
+				Record << "Hash"sv << Key;
+			}
+			Record.EndObject();
+			for (size_t Index = 0; Index < AttachmentSizes.size(); Index++)
+			{
+				IoBuffer		 AttachmentData			  = CreateBinaryCacheValue(AttachmentSizes[Index]);
+				CompressedBuffer CompressedAttachmentData = CompressedBuffer::Compress(SharedBuffer(AttachmentData));
+				Record.AddBinaryAttachment(fmt::format("attachment-{}", Index), CompressedAttachmentData.DecodeRawHash());
+				Result.Attachments[Index] = CompressedAttachmentData;
+			}
+			Result.Record = Record.Save().GetBuffer().AsIoBuffer();
+			Result.Record.SetContentType(ZenContentType::kCbObject);
+		}
+		else
+		{
+			std::string RecordData = fmt::format("{}:{}", Bucket, Key.ToHexString());
+			size_t		TotalSize  = RecordData.length() + 1;
+			for (size_t AttachmentSize : AttachmentSizes)
+			{
+				TotalSize += AttachmentSize;
+			}
+			Result.Record = IoBuffer(TotalSize);
+			char* DataPtr = (char*)Result.Record.MutableData();
+			memcpy(DataPtr, RecordData.c_str(), RecordData.length() + 1);
+			DataPtr += RecordData.length() + 1;
+			for (size_t AttachmentSize : AttachmentSizes)
+			{
+				IoBuffer AttachmentData = CreateBinaryCacheValue(AttachmentSize);
+				memcpy(DataPtr, AttachmentData.GetData(), AttachmentData.GetSize());
+				DataPtr += AttachmentData.GetSize();
+			}
+		}
+		return Result;
+	};
+
+	GcManager			  Gc;
+	CidStore			  CidStore(Gc);
+	ZenCacheNamespace	  Zcs(Gc, TempDir.Path() / "cache");
+	CidStoreConfiguration CidConfig = {.RootDirectory = TempDir.Path() / "cas", .TinyValueThreshold = 1024, .HugeValueThreshold = 4096};
+	CidStore.Initialize(CidConfig);
+
+	auto CreateRecords =
+		[&](bool IsStructured, std::string_view BucketName, const std::vector<IoHash>& Cids, const std::vector<size_t>& AttachmentSizes) {
+			for (const IoHash& Cid : Cids)
+			{
+				CacheRecord Record = CreateCacheRecord(IsStructured, BucketName, Cid, AttachmentSizes);
+				Zcs.Put("mybucket", Cid, {.Value = Record.Record});
+				for (const CompressedBuffer& Attachment : Record.Attachments)
+				{
+					CidStore.AddChunk(Attachment.GetCompressed().Flatten().AsIoBuffer(), Attachment.DecodeRawHash());
+				}
+			}
+		};
+
+	std::vector<size_t> AttachmentSizes = {16, 1000, 2000, 4000, 8000, 64000, 80000};
+
+	std::vector<IoHash> UnstructuredCids{CreateKey(4), CreateKey(5), CreateKey(6)};
+	CreateRecords(false, "mybucket"sv, UnstructuredCids, AttachmentSizes);
+
+	std::vector<IoHash> StructuredCids{CreateKey(1), CreateKey(2), CreateKey(3)};
+	CreateRecords(true, "mybucket"sv, StructuredCids, AttachmentSizes);
+
+	ScrubContext ScrubCtx;
+	Zcs.Scrub(ScrubCtx);
+	CidStore.Scrub(ScrubCtx);
+	CHECK(ScrubCtx.ScrubbedChunks() == (StructuredCids.size() + StructuredCids.size() * AttachmentSizes.size()) + UnstructuredCids.size());
+	CHECK(ScrubCtx.BadCids().GetSize() == 0);
+}
+
+#endif
+
+void
+z$_forcelink()
+{
+}
+
+}  // namespace zen
diff --git a/src/zenserver/cache/structuredcachestore.h b/src/zenserver/cache/structuredcachestore.h
new file mode 100644
index 000000000..3fb4f035d
--- /dev/null
+++ b/src/zenserver/cache/structuredcachestore.h
@@ -0,0 +1,535 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include <zencore/compactbinary.h>
+#include <zencore/iobuffer.h>
+#include <zencore/iohash.h>
+#include <zencore/thread.h>
+#include <zencore/uid.h>
+#include <zenstore/blockstore.h>
+#include <zenstore/caslog.h>
+#include <zenstore/gc.h>
+
+ZEN_THIRD_PARTY_INCLUDES_START
+#include <tsl/robin_map.h>
+ZEN_THIRD_PARTY_INCLUDES_END
+
+#include <atomic>
+#include <compare>
+#include <filesystem>
+#include <unordered_map>
+
+#define ZEN_USE_CACHE_TRACKER 0
+
+namespace zen {
+
+class PathBuilderBase;
+class GcManager;
+class ZenCacheTracker;
+class ScrubContext;
+
+/******************************************************************************
+
+  /$$$$$$$$                        /$$$$$$                   /$$
+ |_____ $$                        /$$__  $$                 | $$
+	  /$$/  /$$$$$$ /$$$$$$$     | $$  \__/ /$$$$$$  /$$$$$$| $$$$$$$  /$$$$$$
+	 /$$/  /$$__  $| $$__  $$    | $$      |____  $$/$$_____| $$__  $$/$$__  $$
+	/$$/  | $$$$$$$| $$  \ $$    | $$       /$$$$$$| $$     | $$  \ $| $$$$$$$$
+   /$$/   | $$_____| $$  | $$    | $$    $$/$$__  $| $$     | $$  | $| $$_____/
+  /$$$$$$$|  $$$$$$| $$  | $$    |  $$$$$$|  $$$$$$|  $$$$$$| $$  | $|  $$$$$$$
+ |________/\_______|__/  |__/     \______/ \_______/\_______|__/  |__/\_______/
+
+  Cache store for UE5. Restricts keys to "{bucket}/{hash}" pairs where the hash
+  is 40 (hex) chars in size. Values may be opaque blobs or structured objects
+  which can in turn contain references to other objects (or blobs).
+
+******************************************************************************/
+
+namespace access_tracking {
+
+	struct KeyAccessTime
+	{
+		IoHash		  Key;
+		GcClock::Tick LastAccess{};
+	};
+
+	struct AccessTimes
+	{
+		std::unordered_map<std::string, std::vector<KeyAccessTime>> Buckets;
+	};
+};	// namespace access_tracking
+
+struct ZenCacheValue
+{
+	IoBuffer Value;
+	uint64_t RawSize = 0;
+	IoHash	 RawHash = IoHash::Zero;
+};
+
+struct CacheValueDetails
+{
+	struct ValueDetails
+	{
+		uint64_t			Size;
+		uint64_t			RawSize;
+		IoHash				RawHash;
+		GcClock::Tick		LastAccess{};
+		std::vector<IoHash> Attachments;
+		ZenContentType		ContentType;
+	};
+
+	struct BucketDetails
+	{
+		std::unordered_map<IoHash, ValueDetails, IoHash::Hasher> Values;
+	};
+
+	struct NamespaceDetails
+	{
+		std::unordered_map<std::string, BucketDetails> Buckets;
+	};
+
+	std::unordered_map<std::string, NamespaceDetails> Namespaces;
+};
+
+//////////////////////////////////////////////////////////////////////////
+
+#pragma pack(push)
+#pragma pack(1)
+
+struct DiskLocation
+{
+	inline DiskLocation() = default;
+
+	inline DiskLocation(uint64_t ValueSize, uint8_t Flags) : Flags(Flags | kStandaloneFile) { Location.StandaloneSize = ValueSize; }
+
+	inline DiskLocation(const BlockStoreLocation& Location, uint64_t PayloadAlignment, uint8_t Flags) : Flags(Flags & ~kStandaloneFile)
+	{
+		this->Location.BlockLocation = BlockStoreDiskLocation(Location, PayloadAlignment);
+	}
+
+	inline BlockStoreLocation GetBlockLocation(uint64_t PayloadAlignment) const
+	{
+		ZEN_ASSERT(!(Flags & kStandaloneFile));
+		return Location.BlockLocation.Get(PayloadAlignment);
+	}
+
+	inline uint64_t		  Size() const { return (Flags & kStandaloneFile) ? Location.StandaloneSize : Location.BlockLocation.GetSize(); }
+	inline uint8_t		  IsFlagSet(uint64_t Flag) const { return Flags & Flag; }
+	inline uint8_t		  GetFlags() const { return Flags; }
+	inline ZenContentType GetContentType() const
+	{
+		ZenContentType ContentType = ZenContentType::kBinary;
+
+		if (IsFlagSet(kStructured))
+		{
+			ContentType = ZenContentType::kCbObject;
+		}
+
+		if (IsFlagSet(kCompressed))
+		{
+			ContentType = ZenContentType::kCompressedBinary;
+		}
+
+		return ContentType;
+	}
+
+	union
+	{
+		BlockStoreDiskLocation BlockLocation;		// 10 bytes
+		uint64_t			   StandaloneSize = 0;	// 8 bytes
+	} Location;
+
+	static const uint8_t kStandaloneFile = 0x80u;  // Stored as a separate file
+	static const uint8_t kStructured	 = 0x40u;  // Serialized as compact binary
+	static const uint8_t kTombStone		 = 0x20u;  // Represents a deleted key/value
+	static const uint8_t kCompressed	 = 0x10u;  // Stored in compressed buffer format
+
+	uint8_t Flags	 = 0;
+	uint8_t Reserved = 0;
+};
+
+struct DiskIndexEntry
+{
+	IoHash		 Key;		// 20 bytes
+	DiskLocation Location;	// 12 bytes
+};
+
+#pragma pack(pop)
+
+static_assert(sizeof(DiskIndexEntry) == 32);
+
+// This store the access time as seconds since epoch internally in a 32-bit value giving is a range of 136 years since epoch
+struct AccessTime
+{
+	explicit AccessTime(GcClock::Tick Tick) noexcept : SecondsSinceEpoch(ToSeconds(Tick)) {}
+	AccessTime& operator=(GcClock::Tick Tick) noexcept
+	{
+		SecondsSinceEpoch.store(ToSeconds(Tick), std::memory_order_relaxed);
+		return *this;
+	}
+	operator GcClock::Tick() const noexcept
+	{
+		return std::chrono::duration_cast<GcClock::Duration>(std::chrono::seconds(SecondsSinceEpoch.load(std::memory_order_relaxed)))
+			.count();
+	}
+
+	AccessTime(AccessTime&& Rhs) noexcept : SecondsSinceEpoch(Rhs.SecondsSinceEpoch.load(std::memory_order_relaxed)) {}
+	AccessTime(const AccessTime& Rhs) noexcept : SecondsSinceEpoch(Rhs.SecondsSinceEpoch.load(std::memory_order_relaxed)) {}
+	AccessTime& operator=(AccessTime&& Rhs) noexcept
+	{
+		SecondsSinceEpoch.store(Rhs.SecondsSinceEpoch.load(std::memory_order_relaxed), std::memory_order_relaxed);
+		return *this;
+	}
+	AccessTime& operator=(const AccessTime& Rhs) noexcept
+	{
+		SecondsSinceEpoch.store(Rhs.SecondsSinceEpoch.load(std::memory_order_relaxed), std::memory_order_relaxed);
+		return *this;
+	}
+
+private:
+	static uint32_t ToSeconds(GcClock::Tick Tick)
+	{
+		return gsl::narrow<uint32_t>(std::chrono::duration_cast<std::chrono::seconds>(GcClock::Duration(Tick)).count());
+	}
+	std::atomic_uint32_t SecondsSinceEpoch;
+};
+
+/** In-memory cache storage
+
+	Intended for small values which are frequently accessed
+
+	This should have a better memory management policy to maintain reasonable
+	footprint.
+ */
+class ZenCacheMemoryLayer
+{
+public:
+	struct Configuration
+	{
+		uint64_t TargetFootprintBytes = 16 * 1024 * 1024;
+		uint64_t ScavengeThreshold	  = 4 * 1024 * 1024;
+	};
+
+	struct BucketInfo
+	{
+		uint64_t EntryCount = 0;
+		uint64_t TotalSize	= 0;
+	};
+
+	struct Info
+	{
+		Configuration			 Config;
+		std::vector<std::string> BucketNames;
+		uint64_t				 EntryCount = 0;
+		uint64_t				 TotalSize	= 0;
+	};
+
+	ZenCacheMemoryLayer();
+	~ZenCacheMemoryLayer();
+
+	bool	 Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
+	void	 Put(std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
+	void	 Drop();
+	bool	 DropBucket(std::string_view Bucket);
+	void	 Scrub(ScrubContext& Ctx);
+	void	 GatherAccessTimes(zen::access_tracking::AccessTimes& AccessTimes);
+	void	 Reset();
+	uint64_t TotalSize() const;
+
+	Info					  GetInfo() const;
+	std::optional<BucketInfo> GetBucketInfo(std::string_view Bucket) const;
+
+	const Configuration& GetConfiguration() const { return m_Configuration; }
+	void				 SetConfiguration(const Configuration& NewConfig) { m_Configuration = NewConfig; }
+
+private:
+	struct CacheBucket
+	{
+#pragma pack(push)
+#pragma pack(1)
+		struct BucketPayload
+		{
+			IoBuffer Payload;  // 8
+			uint32_t RawSize;  // 4
+			IoHash	 RawHash;  // 20
+		};
+#pragma pack(pop)
+		static_assert(sizeof(BucketPayload) == 32u);
+		static_assert(sizeof(AccessTime) == 4u);
+
+		mutable RwLock					 m_BucketLock;
+		std::vector<AccessTime>			 m_AccessTimes;
+		std::vector<BucketPayload>		 m_Payloads;
+		tsl::robin_map<IoHash, uint32_t> m_CacheMap;
+
+		std::atomic_uint64_t m_TotalSize{};
+
+		bool			Get(const IoHash& HashKey, ZenCacheValue& OutValue);
+		void			Put(const IoHash& HashKey, const ZenCacheValue& Value);
+		void			Drop();
+		void			Scrub(ScrubContext& Ctx);
+		void			GatherAccessTimes(std::vector<zen::access_tracking::KeyAccessTime>& AccessTimes);
+		inline uint64_t TotalSize() const { return m_TotalSize; }
+		uint64_t		EntryCount() const;
+	};
+
+	mutable RwLock												  m_Lock;
+	std::unordered_map<std::string, std::unique_ptr<CacheBucket>> m_Buckets;
+	std::vector<std::unique_ptr<CacheBucket>>					  m_DroppedBuckets;
+	Configuration												  m_Configuration;
+
+	ZenCacheMemoryLayer(const ZenCacheMemoryLayer&) = delete;
+	ZenCacheMemoryLayer& operator=(const ZenCacheMemoryLayer&) = delete;
+};
+
+class ZenCacheDiskLayer
+{
+public:
+	struct Configuration
+	{
+		std::filesystem::path RootDir;
+	};
+
+	struct BucketInfo
+	{
+		uint64_t EntryCount = 0;
+		uint64_t TotalSize	= 0;
+	};
+
+	struct Info
+	{
+		Configuration			 Config;
+		std::vector<std::string> BucketNames;
+		uint64_t				 EntryCount = 0;
+		uint64_t				 TotalSize	= 0;
+	};
+
+	explicit ZenCacheDiskLayer(const std::filesystem::path& RootDir);
+	~ZenCacheDiskLayer();
+
+	bool Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
+	void Put(std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
+	bool Drop();
+	bool DropBucket(std::string_view Bucket);
+	void Flush();
+	void Scrub(ScrubContext& Ctx);
+	void GatherReferences(GcContext& GcCtx);
+	void CollectGarbage(GcContext& GcCtx);
+	void UpdateAccessTimes(const zen::access_tracking::AccessTimes& AccessTimes);
+
+	void	 DiscoverBuckets();
+	uint64_t TotalSize() const;
+
+	Info					  GetInfo() const;
+	std::optional<BucketInfo> GetBucketInfo(std::string_view Bucket) const;
+
+	CacheValueDetails::NamespaceDetails GetValueDetails(const std::string_view BucketFilter, const std::string_view ValueFilter) const;
+
+private:
+	/** A cache bucket manages a single directory containing
+		metadata and data for that bucket
+	  */
+	struct CacheBucket
+	{
+		CacheBucket(std::string BucketName);
+		~CacheBucket();
+
+		bool OpenOrCreate(std::filesystem::path BucketDir, bool AllowCreate = true);
+		bool Get(const IoHash& HashKey, ZenCacheValue& OutValue);
+		void Put(const IoHash& HashKey, const ZenCacheValue& Value);
+		bool Drop();
+		void Flush();
+		void Scrub(ScrubContext& Ctx);
+		void GatherReferences(GcContext& GcCtx);
+		void CollectGarbage(GcContext& GcCtx);
+		void UpdateAccessTimes(const std::vector<zen::access_tracking::KeyAccessTime>& AccessTimes);
+
+		inline uint64_t TotalSize() const { return m_TotalStandaloneSize.load(std::memory_order::relaxed) + m_BlockStore.TotalSize(); }
+		uint64_t		EntryCount() const;
+
+		CacheValueDetails::BucketDetails GetValueDetails(const std::string_view ValueFilter) const;
+
+	private:
+		const uint64_t MaxBlockSize		  = 1ull << 30;
+		uint64_t	   m_PayloadAlignment = 1ull << 4;
+
+		std::string			  m_BucketName;
+		std::filesystem::path m_BucketDir;
+		std::filesystem::path m_BlocksBasePath;
+		BlockStore			  m_BlockStore;
+		Oid					  m_BucketId;
+		uint64_t			  m_LargeObjectThreshold = 128 * 1024;
+
+		// These files are used to manage storage of small objects for this bucket
+
+		TCasLogFile<DiskIndexEntry> m_SlogFile;
+		uint64_t					m_LogFlushPosition = 0;
+
+#pragma pack(push)
+#pragma pack(1)
+		struct BucketPayload
+		{
+			DiskLocation Location;	// 12
+			uint64_t	 RawSize;	// 8
+			IoHash		 RawHash;	// 20
+		};
+#pragma pack(pop)
+		static_assert(sizeof(BucketPayload) == 40u);
+		static_assert(sizeof(AccessTime) == 4u);
+
+		using IndexMap = tsl::robin_map<IoHash, size_t, IoHash::Hasher>;
+
+		mutable RwLock			   m_IndexLock;
+		std::vector<AccessTime>	   m_AccessTimes;
+		std::vector<BucketPayload> m_Payloads;
+		IndexMap				   m_Index;
+
+		std::atomic_uint64_t m_TotalStandaloneSize{};
+
+		void							BuildPath(PathBuilderBase& Path, const IoHash& HashKey) const;
+		void							PutStandaloneCacheValue(const IoHash& HashKey, const ZenCacheValue& Value);
+		IoBuffer						GetStandaloneCacheValue(const DiskLocation& Loc, const IoHash& HashKey) const;
+		void							PutInlineCacheValue(const IoHash& HashKey, const ZenCacheValue& Value);
+		IoBuffer						GetInlineCacheValue(const DiskLocation& Loc) const;
+		void							MakeIndexSnapshot();
+		uint64_t						ReadIndexFile(const std::filesystem::path& IndexPath, uint32_t& OutVersion);
+		uint64_t						ReadLog(const std::filesystem::path& LogPath, uint64_t LogPosition);
+		void							OpenLog(const bool IsNew);
+		void							SaveManifest();
+		CacheValueDetails::ValueDetails GetValueDetails(const IoHash& Key, size_t Index) const;
+		// These locks are here to avoid contention on file creation, therefore it's sufficient
+		// that we take the same lock for the same hash
+		//
+		// These locks are small and should really be spaced out so they don't share cache lines,
+		// but we don't currently access them at particularly high frequency so it should not be
+		// an issue in practice
+
+		mutable RwLock m_ShardedLocks[256];
+		inline RwLock& LockForHash(const IoHash& Hash) const { return m_ShardedLocks[Hash.Hash[19]]; }
+	};
+
+	std::filesystem::path										  m_RootDir;
+	mutable RwLock												  m_Lock;
+	std::unordered_map<std::string, std::unique_ptr<CacheBucket>> m_Buckets;  // TODO: make this case insensitive
+	std::vector<std::unique_ptr<CacheBucket>>					  m_DroppedBuckets;
+
+	ZenCacheDiskLayer(const ZenCacheDiskLayer&) = delete;
+	ZenCacheDiskLayer& operator=(const ZenCacheDiskLayer&) = delete;
+};
+
+class ZenCacheNamespace final : public RefCounted, public GcStorage, public GcContributor
+{
+public:
+	struct Configuration
+	{
+		std::filesystem::path RootDir;
+		uint64_t			  DiskLayerThreshold = 0;
+	};
+	struct BucketInfo
+	{
+		ZenCacheDiskLayer::BucketInfo	DiskLayerInfo;
+		ZenCacheMemoryLayer::BucketInfo MemoryLayerInfo;
+	};
+	struct Info
+	{
+		Configuration			  Config;
+		std::vector<std::string>  BucketNames;
+		ZenCacheDiskLayer::Info	  DiskLayerInfo;
+		ZenCacheMemoryLayer::Info MemoryLayerInfo;
+	};
+
+	ZenCacheNamespace(GcManager& Gc, const std::filesystem::path& RootDir);
+	~ZenCacheNamespace();
+
+	bool					  Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
+	void					  Put(std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
+	bool					  Drop();
+	bool					  DropBucket(std::string_view Bucket);
+	void					  Flush();
+	void					  Scrub(ScrubContext& Ctx);
+	uint64_t				  DiskLayerThreshold() const { return m_DiskLayerSizeThreshold; }
+	virtual void			  GatherReferences(GcContext& GcCtx) override;
+	virtual void			  CollectGarbage(GcContext& GcCtx) override;
+	virtual GcStorageSize	  StorageSize() const override;
+	Info					  GetInfo() const;
+	std::optional<BucketInfo> GetBucketInfo(std::string_view Bucket) const;
+
+	CacheValueDetails::NamespaceDetails GetValueDetails(const std::string_view BucketFilter, const std::string_view ValueFilter) const;
+
+private:
+	std::filesystem::path m_RootDir;
+	ZenCacheMemoryLayer	  m_MemLayer;
+	ZenCacheDiskLayer	  m_DiskLayer;
+	uint64_t			  m_DiskLayerSizeThreshold = 1 * 1024;
+	uint64_t			  m_LastScrubTime		   = 0;
+
+#if ZEN_USE_CACHE_TRACKER
+	std::unique_ptr<ZenCacheTracker> m_AccessTracker;
+#endif
+
+	ZenCacheNamespace(const ZenCacheNamespace&) = delete;
+	ZenCacheNamespace& operator=(const ZenCacheNamespace&) = delete;
+};
+
+class ZenCacheStore final
+{
+public:
+	static constexpr std::string_view DefaultNamespace =
+		"!default!";  // This is intentionally not a valid namespace name and will only be used for mapping when no namespace is given
+	static constexpr std::string_view NamespaceDiskPrefix = "ns_";
+
+	struct Configuration
+	{
+		std::filesystem::path BasePath;
+		bool				  AllowAutomaticCreationOfNamespaces = false;
+	};
+
+	struct Info
+	{
+		Configuration			 Config;
+		std::vector<std::string> NamespaceNames;
+		uint64_t				 DiskEntryCount	  = 0;
+		uint64_t				 MemoryEntryCount = 0;
+		GcStorageSize			 StorageSize;
+	};
+
+	ZenCacheStore(GcManager& Gc, const Configuration& Configuration);
+	~ZenCacheStore();
+
+	bool Get(std::string_view Namespace, std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
+	void Put(std::string_view Namespace, std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
+	bool DropBucket(std::string_view Namespace, std::string_view Bucket);
+	bool DropNamespace(std::string_view Namespace);
+	void Flush();
+	void Scrub(ScrubContext& Ctx);
+
+	CacheValueDetails GetValueDetails(const std::string_view NamespaceFilter,
+									  const std::string_view BucketFilter,
+									  const std::string_view ValueFilter) const;
+
+	GcStorageSize StorageSize() const;
+	//	const Configuration& GetConfiguration() const { return m_Configuration; }
+
+	Info										 GetInfo() const;
+	std::optional<ZenCacheNamespace::Info>		 GetNamespaceInfo(std::string_view Namespace);
+	std::optional<ZenCacheNamespace::BucketInfo> GetBucketInfo(std::string_view Namespace, std::string_view Bucket);
+
+private:
+	const ZenCacheNamespace* FindNamespace(std::string_view Namespace) const;
+	ZenCacheNamespace*		 GetNamespace(std::string_view Namespace);
+	void IterateNamespaces(const std::function<void(std::string_view Namespace, ZenCacheNamespace& Store)>& Callback) const;
+
+	typedef std::unordered_map<std::string, std::unique_ptr<ZenCacheNamespace>> NamespaceMap;
+
+	mutable RwLock									m_NamespacesLock;
+	NamespaceMap									m_Namespaces;
+	std::vector<std::unique_ptr<ZenCacheNamespace>> m_DroppedNamespaces;
+
+	GcManager&	  m_Gc;
+	Configuration m_Configuration;
+};
+
+void z$_forcelink();
+
+}  // namespace zen