diff --git a/.github/workflows/runner-full-stack-e2e.yml b/.github/workflows/runner-full-stack-e2e.yml
index fc3c18f31d..c1bf863766 100644
--- a/.github/workflows/runner-full-stack-e2e.yml
+++ b/.github/workflows/runner-full-stack-e2e.yml
@@ -553,33 +553,48 @@ jobs:
             -f "ref=$GITHUB_WORKFLOW_SHA" --jq .sha)"
           [[ "$workflow_blob" =~ ^[0-9a-f]{40}$ ]]
 
+          package_set_manifest="$RUNNER_TEMP/runner-e2e-build-packages"
+          dpkg-query --show --showformat='${binary:Package}=${Version}\n' \
+            | LC_ALL=C sort > "$package_set_manifest"
+          test -s "$package_set_manifest"
+          package_set_id="$(sha256sum "$package_set_manifest" | cut -d ' ' -f 1)"
+          [[ "$package_set_id" =~ ^[0-9a-f]{64}$ ]]
+
           toolchain_id="$({
-            printf '%s\n' 'paperclip-runner/e2e-build-toolchain/v1'
+            printf '%s\n' 'paperclip-runner/e2e-build-toolchain/v2'
             printf 'runner=%s\n' "$TEST_RUNNER"
             printf 'runner-os=%s\n' "$RUNNER_OS"
             printf 'runner-arch=%s\n' "$RUNNER_ARCH"
+            printf 'runner-image-os=%s\n' "${ImageOS-}"
+            printf 'runner-image-version=%s\n' "${ImageVersion-}"
+            printf 'package-set=%s\n' "$package_set_id"
             for variable in \
-              CC CFLAGS CI CARGO_BUILD_TARGET CARGO_ENCODED_RUSTFLAGS \
+              AR CC CFLAGS CI CMAKE CARGO_BUILD_TARGET CARGO_ENCODED_RUSTFLAGS \
               CARGO_TARGET_DIR LANG LC_ALL LDFLAGS NODE_ENV NODE_OPTIONS \
-              RUSTC RUSTC_WRAPPER RUSTFLAGS SOURCE_DATE_EPOCH TZ
+              CXX PKG_CONFIG RANLIB RUSTC RUSTC_WRAPPER RUSTFLAGS \
+              SOURCE_DATE_EPOCH TZ
             do
               printf '%s=%s\n' "$variable" "${!variable-}"
             done
             uname -srm
-            sha256sum /etc/os-release "$(command -v cc)" "$(command -v ld)" "$(command -v ldd)"
+            sha256sum /etc/os-release
             node --version
             pnpm --version
             (cd packages/paperclip-runner && rustc -vV)
             (cd packages/paperclip-runner && cargo -Vv)
-            cc --version
-            ld --version
-            ldd --version
+            for tool in cc c++ ld ldd ar ranlib cmake pkg-config; do
+              tool_path="$(command -v "$tool")"
+              test -f "$tool_path"
+              printf 'tool=%s path=%s\n' "$tool" "$tool_path"
+              sha256sum "$tool_path"
+              "$tool" --version
+            done
           } | sha256sum | cut -d ' ' -f 1)"
           [[ "$toolchain_id" =~ ^[0-9a-f]{64}$ ]]
 
           manifest="$RUNNER_TEMP/runner-e2e-build-inputs"
           {
-            printf '%s\n' 'paperclip-runner/e2e-build-inputs/v1'
+            printf '%s\n' 'paperclip-runner/e2e-build-inputs/v2'
             printf 'workflow=%s\n' "$workflow_blob"
             printf 'lock=%s\n' "$EXPECTED_LOCK_SHA256"
             printf 'toolchain=%s\n' "$toolchain_id"
@@ -612,7 +627,7 @@ jobs:
           {
             echo "content_id=$content_id"
             echo "toolchain_id=$toolchain_id"
-            echo "cache_key=runner-e2e-build-v1-$ref_scope-$content_id"
+            echo "cache_key=runner-e2e-build-v2-$ref_scope-$content_id"
           } >> "$GITHUB_OUTPUT"
 
       - name: Restore exact reusable build outputs
diff --git a/tests/runner-e2e/README.md b/tests/runner-e2e/README.md
index ad62738f60..f10c8114e5 100644
--- a/tests/runner-e2e/README.md
+++ b/tests/runner-e2e/README.md
@@ -341,6 +341,14 @@ default of 32. Multi-turn steps are sequential inside their cell while
 independent cells overlap. Artifacts and merged HTML/JUnit/normalized reports
 are retained for 30 days.
 
+The campaign builds shared TypeScript and native runner outputs once and then
+fans that verified bundle out to selected cells. A later campaign on the same
+target branch may reuse the bundle only when the trusted workflow, target
+source closure and lockfile, requested output shape, runner image package set,
+and native toolchain identity are exact matches. Changes to native build tools
+such as CMake, pkg-config, the compiler, archiver, or ranlib deliberately force
+a cold rebuild.
+
 Restrict the RunsOn fleet to this repository and independently trusted
 workflows. Do not let untrusted pull-request or fork-triggered workflows target
 it, and require a fresh ephemeral instance for each job so one paid cell cannot
diff --git a/tests/runner-e2e/SECURITY.md b/tests/runner-e2e/SECURITY.md
index 518e9f1a47..87b0a4aafc 100644
--- a/tests/runner-e2e/SECURITY.md
+++ b/tests/runner-e2e/SECURITY.md
@@ -38,6 +38,15 @@ history publication explicitly use the trusted workflow commit and do not
 consume the target lockfile. Never run the workflow definition from the target
 branch.
 
+Reusable executable build outputs are keyed by the trusted workflow blob, the
+resolved target lockfile, a conservative source closure, requested output
+shape, target branch scope, and the build environment. The environment identity
+includes the literal runner selector, OS and architecture, the sorted installed
+Debian package set, and the resolved path, digest, and version output of the C,
+C++, linker, archiver, ranlib, CMake, and pkg-config tools. This is intentionally
+conservative: a runner image or native build-package update must produce a cold
+cache miss rather than reusing binaries from an under-specified toolchain.
+
 The workflows verify both the original actor and triggering actor for every
 scheduled or manual attempt, including human reruns. Every
 secret-bearing job repeats this check as its first step so GitHub's partial-job
diff --git a/tests/runner-e2e/workflow-security.test.ts b/tests/runner-e2e/workflow-security.test.ts
index 850b245394..561a28b29e 100644
--- a/tests/runner-e2e/workflow-security.test.ts
+++ b/tests/runner-e2e/workflow-security.test.ts
@@ -549,10 +549,10 @@ describe("public repository paid workflow security", () => {
     );
     expect(runnerBuildJob).not.toContain("restore-keys:");
     expect(runnerBuildJob).toContain(
-      "cache_key=runner-e2e-build-v1-$ref_scope-$content_id",
+      "cache_key=runner-e2e-build-v2-$ref_scope-$content_id",
     );
     expect(runnerBuildJob).not.toContain(
-      "cache_key=runner-e2e-build-v1-$TARGET_SHA",
+      "cache_key=runner-e2e-build-v2-$TARGET_SHA",
     );
     expect(runnerBuildJob).toContain(
       '"repos/$REPOSITORY/contents/.github/workflows/runner-full-stack-e2e.yml"',
@@ -593,21 +593,38 @@ describe("public repository paid workflow security", () => {
       "@paperclipai/paperclip-eval-kernel",
     ]);
     for (const toolchainInput of [
+      "paperclip-runner/e2e-build-toolchain/v2",
+      "paperclip-runner/e2e-build-inputs/v2",
+      "AR CC CFLAGS",
       "CARGO_ENCODED_RUSTFLAGS",
+      "CMAKE",
+      "CXX",
       "NODE_OPTIONS",
+      "PKG_CONFIG",
+      "RANLIB",
       "RUSTFLAGS",
       "uname -srm",
-      'sha256sum /etc/os-release "$(command -v cc)"',
+      "runner-image-os=",
+      "runner-image-version=",
+      "dpkg-query --show --showformat=",
+      "package-set=%s",
+      'for tool in cc c++ ld ldd ar ranlib cmake pkg-config; do',
+      'tool_path="$(command -v "$tool")"',
+      'sha256sum "$tool_path"',
       "node --version",
       "pnpm --version",
       "rustc -vV",
       "cargo -Vv",
-      "cc --version",
-      "ld --version",
-      "ldd --version",
+      '"$tool" --version',
     ]) {
       expect(runnerBuildJob).toContain(toolchainInput);
     }
+    expect(runnerBuildJob).not.toContain(
+      "paperclip-runner/e2e-build-toolchain/v1",
+    );
+    expect(runnerBuildJob).not.toContain(
+      "paperclip-runner/e2e-build-inputs/v1",
+    );
     expect(
       runnerBuildJob.match(
         /if: steps\.restore_build_cache\.outputs\.cache-hit != 'true'/gu,