diff --git a/install.sh b/install.sh
index bea1786..c789cca 100755
--- a/install.sh
+++ b/install.sh
@@ -45,7 +45,7 @@ import urllib.request
 KEY = "local.frameyap.overlay"
 # The pinned release this installer belongs to (set in the release commit that
 # is tagged vRELEASE_VERSION); empty in a development tree.
-RELEASE_VERSION = "0.1.202610050143"
+RELEASE_VERSION = "0.1.202610050153"
 MARKER = "# FrameYap managed launcher v1\n"
 ARCHIVE_LIMIT = 12 * 1024**3
 MEMBER_LIMIT = 50000
diff --git a/scripts/install_payload.py b/scripts/install_payload.py
index c07f3bf..4d11bf7 100644
--- a/scripts/install_payload.py
+++ b/scripts/install_payload.py
@@ -25,7 +25,7 @@ import urllib.request
 KEY = "local.frameyap.overlay"
 # The pinned release this installer belongs to (set in the release commit that
 # is tagged vRELEASE_VERSION); empty in a development tree.
-RELEASE_VERSION = "0.1.202610050143"
+RELEASE_VERSION = "0.1.202610050153"
 MARKER = "# FrameYap managed launcher v1\n"
 ARCHIVE_LIMIT = 12 * 1024**3
 MEMBER_LIMIT = 50000
diff --git a/scripts/model-status.py b/scripts/model-status.py
index ef6a958..f5209a8 100755
--- a/scripts/model-status.py
+++ b/scripts/model-status.py
@@ -5,6 +5,8 @@ import json
 from pathlib import Path
 import sys
 
+# Installed release inventories must remain unchanged by status queries.
+sys.dont_write_bytecode = True
 sys.path.insert(0, str(Path(__file__).resolve().parents[1] / "python"))
 from frameyap.model_files import DEFAULT_MANIFEST_DIR, ManifestError, check_model, load_backends
 
diff --git a/src/model_status.cpp b/src/model_status.cpp
index b2f2400..8f9e6fb 100644
--- a/src/model_status.cpp
+++ b/src/model_status.cpp
@@ -29,7 +29,7 @@ int model_status(const CliOptions& options, const char* executable) {
         script = fs::path(FRAMEYAP_SOURCE_ROOT) / "scripts/model-status.py";
     if (!fs::is_regular_file(script))
         throw std::runtime_error("model-status.py missing beside application layout: " + script.string());
-    std::vector<std::string> args{"python3", script.string()};
+    std::vector<std::string> args{"python3", "-B", script.string()};
     if (options.mode == CliMode::ListModels) args.emplace_back("--list-models");
     else { args.emplace_back("--check-model"); args.push_back(options.model_id); }
     if (!options.model_dir.empty()) { args.emplace_back("--model-dir"); args.push_back(options.model_dir); }
diff --git a/tests/model_status.cmake b/tests/model_status.cmake
index a3243ef..e48191c 100644
--- a/tests/model_status.cmake
+++ b/tests/model_status.cmake
@@ -12,6 +12,8 @@ check("${APP}" 0 "\"schema\": 1.*\"models\"|\"models\".*\"schema\": 1" --list-mo
 check("${APP}" 1 "\"state\": \"not_installed\"" --check-model redux --model-dir "${STAGE}/absent" --json)
 check("${APP}" 2 "^$" --check-model "redux;echo" --model-dir "${STAGE}/absent" --json)
 check("${APP}" 2 "^$" --check-model "../redux" --model-dir "${STAGE}/absent" --json)
+# Remove the previous fixture, including caches left by older test runs.
+file(REMOVE_RECURSE "${STAGE}")
 # Minimal installed payload, independent of the source tree's script/module/asset paths.
 file(MAKE_DIRECTORY "${STAGE}/bin" "${STAGE}/scripts" "${STAGE}/python/frameyap" "${STAGE}/assets/backends")
 file(COPY "${APP}" DESTINATION "${STAGE}/bin")
@@ -41,3 +43,14 @@ check("${STAGE}/bin/${name}" 0 "\"state\": \"installed_verified\""
 file(WRITE "${STAGE}/models/toy/weights.bin" "HELLO")
 check("${STAGE}/bin/${name}" 1 "\"reason\": \"hash_mismatch\""
   --check-model toy --manifest-dir "${STAGE}/fixtures" --model-dir "${STAGE}/models/toy" --json)
+
+# The standalone script must also preserve the inventory without the launcher.
+execute_process(COMMAND python3 "${STAGE}/scripts/model-status.py" --list-models
+  RESULT_VARIABLE standalone_status OUTPUT_QUIET ERROR_VARIABLE standalone_error)
+if(NOT standalone_status EQUAL 0)
+  message(FATAL_ERROR "Standalone model status failed: ${standalone_error}")
+endif()
+file(GLOB_RECURSE generated_cache "${STAGE}/python/*.pyc")
+if(generated_cache OR EXISTS "${STAGE}/python/frameyap/__pycache__")
+  message(FATAL_ERROR "Offline model status modified the installed release: ${generated_cache}")
+endif()