8 files changed, 70 insertions, 4 deletions
diff --git a/scripts/test_scripts/builds-download-upload-test.py b/scripts/test_scripts/builds-download-upload-test.py
index 8ff5245c1..dd9aae07e 100644
--- a/scripts/test_scripts/builds-download-upload-test.py
+++ b/scripts/test_scripts/builds-download-upload-test.py
@@ -82,7 +82,7 @@ SERVER_ARGS: tuple[str, ...] = (
 
 def zen_cmd(*args: str | Path, extra_zen_args: list[str] | None = None) -> list[str | Path]:
     """Build a zen CLI command list, inserting extra_zen_args before subcommands."""
-    return [ZEN_EXE, *(extra_zen_args or []), *args]
+    return [ZEN_EXE, "--enable-execution-history=false", *(extra_zen_args or []), *args]
 
 
 def run(cmd: list[str | Path]) -> None:
diff --git a/scripts/test_scripts/builds-download-upload-update-build-ids.py b/scripts/test_scripts/builds-download-upload-update-build-ids.py
index 2a63aa44d..6332d6990 100644
--- a/scripts/test_scripts/builds-download-upload-update-build-ids.py
+++ b/scripts/test_scripts/builds-download-upload-update-build-ids.py
@@ -51,7 +51,7 @@ def list_builds_for_bucket(zen: str, host: str, namespace: str, bucket: str) ->
         result_path = Path(tmp.name)
 
     cmd = [
-        zen, "builds", "list",
+        zen, "--enable-execution-history=false", "builds", "list",
         "--namespace", namespace,
         "--bucket", bucket,
         "--host", host,
diff --git a/scripts/test_scripts/hub_load_test.py b/scripts/test_scripts/hub_load_test.py
index 7bff1eb37..33f05d90f 100644
--- a/scripts/test_scripts/hub_load_test.py
+++ b/scripts/test_scripts/hub_load_test.py
@@ -183,6 +183,7 @@ def _start_hub(
     cmd = [
         str(zenserver_exe),
         "hub",
+        "--enable-execution-history=false",
         f"--data-dir={data_dir}",
         f"--port={port}",
         "--hub-instance-http-threads=8",
diff --git a/scripts/test_scripts/hub_provision_perf_test.py b/scripts/test_scripts/hub_provision_perf_test.py
index 5b264ad62..76fb8508d 100644
--- a/scripts/test_scripts/hub_provision_perf_test.py
+++ b/scripts/test_scripts/hub_provision_perf_test.py
@@ -205,6 +205,7 @@ def _start_hub(
     cmd = [
         str(zenserver_exe),
         "hub",
+        "--enable-execution-history=false",
         f"--data-dir={data_dir}",
         f"--port={port}",
         "--hub-instance-http-threads=8",
diff --git a/scripts/test_scripts/kill-test-processes.ps1 b/scripts/test_scripts/kill-test-processes.ps1
new file mode 100644
index 000000000..0668a5319
--- /dev/null
+++ b/scripts/test_scripts/kill-test-processes.ps1
@@ -0,0 +1,19 @@
+# Kill leftover CI test processes (zenserver, minio, nomad, consul) whose
+# executable lives under the given build directory. Windows counterpart of
+# kill-test-processes.sh; see that file for rationale.
+#
+# Usage: kill-test-processes.ps1 -Label <label> -BuildDir <path>
+
+param(
+  [Parameter(Mandatory=$true)][string]$Label,
+  [Parameter(Mandatory=$true)][string]$BuildDir
+)
+
+foreach ($name in @('zenserver', 'minio', 'nomad', 'consul')) {
+  $procs = Get-Process -Name $name -ErrorAction SilentlyContinue |
+    Where-Object { $_.Path -and $_.Path.StartsWith($BuildDir, [System.StringComparison]::OrdinalIgnoreCase) }
+  foreach ($p in $procs) {
+    Write-Host "Killing $Label $name (PID $($p.Id)): $($p.Path)"
+    $p | Stop-Process -Force -ErrorAction SilentlyContinue
+  }
+}
diff --git a/scripts/test_scripts/kill-test-processes.sh b/scripts/test_scripts/kill-test-processes.sh
new file mode 100755
index 000000000..e5fb2fcaa
--- /dev/null
+++ b/scripts/test_scripts/kill-test-processes.sh
@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+#
+# Kill leftover CI test processes (zenserver, minio, nomad, consul) whose
+# executable lives under the given build directory.
+#
+# Used by CI workflows to clean up any test processes from a previous run
+# before starting a new one, and to reap any that are still running after
+# the run finishes.
+#
+# Usage: kill-test-processes.sh <label> <build_dir>
+#   label:     word printed in log messages, e.g. "stale" or "leftover"
+#   build_dir: absolute path; only processes whose executable is under this
+#              directory are killed.
+#
+# We resolve each PID's actual executable path rather than relying on argv
+# (which `pgrep -a` reports). argv starts with the short process name (e.g.
+# "consul") regardless of how the process was launched, so a pure argv prefix
+# match never fires and leftovers silently survived between runs.
+
+set -u
+
+label=${1:?label required}
+build_dir=${2:?build_dir required}
+
+get_exe_path() {
+  local pid=$1
+  if [[ -r "/proc/$pid/exe" ]]; then
+    # Linux
+    readlink -f "/proc/$pid/exe" 2>/dev/null || true
+  else
+    # macOS fallback: the "txt" file descriptor points at the process binary
+    lsof -p "$pid" -Fn -a -d txt 2>/dev/null | awk '/^n/{print substr($0,2); exit}' || true
+  fi
+}
+
+for name in zenserver minio nomad consul; do
+  while read -r pid; do
+    [[ -z "$pid" ]] && continue
+    exe=$(get_exe_path "$pid")
+    if [[ "$exe" == "$build_dir"* ]]; then
+      echo "Killing $label $name (PID $pid): $exe"
+      kill -9 "$pid" 2>/dev/null || true
+    fi
+  done < <(pgrep -x "$name" 2>/dev/null || true)
+done
diff --git a/scripts/test_scripts/oplog-import-export-test.py b/scripts/test_scripts/oplog-import-export-test.py
index f913a7351..93f732135 100644
--- a/scripts/test_scripts/oplog-import-export-test.py
+++ b/scripts/test_scripts/oplog-import-export-test.py
@@ -82,7 +82,7 @@ SERVER_ARGS: tuple[str, ...] = (
 
 def zen_cmd(*args: str | Path, extra_zen_args: list[str] | None = None) -> list[str | Path]:
     """Build a zen CLI command list, inserting extra_zen_args before subcommands."""
-    return [ZEN_EXE, *(extra_zen_args or []), *args]
+    return [ZEN_EXE, "--enable-execution-history=false", *(extra_zen_args or []), *args]
 
 
 def run(cmd: list[str | Path]) -> None:
diff --git a/scripts/test_scripts/oplog-update-build-ids.py b/scripts/test_scripts/oplog-update-build-ids.py
index 67e128c8e..2675d07c0 100644
--- a/scripts/test_scripts/oplog-update-build-ids.py
+++ b/scripts/test_scripts/oplog-update-build-ids.py
@@ -52,7 +52,7 @@ def list_builds_for_bucket(zen: str, host: str, namespace: str, bucket: str) ->
         result_path = Path(tmp.name)
 
     cmd = [
-        zen, "builds", "list",
+        zen, "--enable-execution-history=false", "builds", "list",
         "--namespace", namespace,
         "--bucket", bucket,
         "--host", host,