diff --git a/packages/create-objectstack/src/template-consistency.test.ts b/packages/create-objectstack/src/template-consistency.test.ts
index 466f305d7a6..36ab445bd90 100644
--- a/packages/create-objectstack/src/template-consistency.test.ts
+++ b/packages/create-objectstack/src/template-consistency.test.ts
@@ -14,6 +14,7 @@ import { fileURLToPath } from 'node:url';
 import { syncObjectStackDeps } from './pkg-utils.js';
 import { copyDir, TEMPLATE_FILE_ALIASES } from './template-copy.js';
 import { TEMPLATES } from './template-registry.js';
+import { gitFreeEnv } from '../../../scripts/git-env.mjs';
 import { SKILLS_CATALOG, SKILLS_INSTALL_COMMAND } from './skills-install.js';
 
 const pkgRoot = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
@@ -52,26 +53,32 @@ const REGISTRY_SOURCE = fs.readFileSync(path.join(pkgRoot, 'src', 'index.ts'), '
 //     read a checkout owned by another user inside a container. Closing it could
 //     turn a passing read into `detected dubious ownership`, which is a
 //     regression this file gets no isolation benefit in exchange for.
-const LEAKED_GIT_ENV = [
-  'GIT_DIR',
-  'GIT_WORK_TREE',
-  'GIT_COMMON_DIR',
-  'GIT_INDEX_FILE',
-  'GIT_OBJECT_DIRECTORY',
-  'GIT_ALTERNATE_OBJECT_DIRECTORIES',
-  'GIT_NAMESPACE',
-  'GIT_CEILING_DIRECTORIES',
-  'GIT_TEMPLATE_DIR',
-  'GIT_CONFIG',
-] as const;
+//
+// #16644 — the hand-maintained allowlist of ten location variables that used to
+// stand here is retired in favour of the blanket strip in `scripts/git-env.mjs`,
+// and it is not re-spelled anywhere in this file so that a census of the retired
+// shape does not match this paragraph. The reason the list goes rather than gets
+// one more entry: it had to be kept level with git's own list of location
+// variables, and its failure mode is that THE KEY IT MISSES IS THE KEY THAT
+// BITES. ⛔ One spelling in the repo, not two — no "either is fine" transition
+// state.
+//
+// `gitFreeEnv()` removes every `GIT_`-prefixed key, which is strictly wider than
+// the list it replaces and still inside the boundary drawn above. It DELETES
+// keys rather than pinning any of them to `/dev/null`, so it never sets
+// `GIT_CONFIG_GLOBAL`: global and system config stay open and `safe.directory`
+// with them, which is the whole of the concern in the bullet above — preserved,
+// and more strictly, because the deletion moves git toward its own defaults
+// instead of substituting an empty config file. The widening is free here for
+// the other reason the module's header names: both children below are LOCAL
+// reads — `ls-files` and `git grep` against `cwd` — so the transport settings
+// the strip also takes (`GIT_CONFIG_*` rewriting remotes, `GIT_SSL_*`) are
+// nothing either one needs. ⛔ A child that fetches, clones or pushes would not
+// be entitled to this environment.
 
 /** The environment the repo-reading git calls below get: this process's, minus
  *  every variable that could aim them at a different repository. */
-const REPO_READ_ENV: NodeJS.ProcessEnv = (() => {
-  const env = { ...process.env };
-  for (const key of LEAKED_GIT_ENV) delete env[key];
-  return env;
-})();
+const REPO_READ_ENV: NodeJS.ProcessEnv = gitFreeEnv();
 
 // ── Declared version surfaces, per bundled template (#9264) ─────────────────
 //
diff --git a/scripts/cross-package-test-inputs.mjs b/scripts/cross-package-test-inputs.mjs
index b2b9cb54b56..b790c2e0c59 100644
--- a/scripts/cross-package-test-inputs.mjs
+++ b/scripts/cross-package-test-inputs.mjs
@@ -1393,6 +1393,23 @@ export const CROSS_PACKAGE_TEST_INPUTS = {
       // with ERR_MODULE_NOT_FOUND), which is exactly the trigger radius this
       // declaration exists to keep honest.
       'scripts/invoked-as.mjs',
+      // The git-environment strip, IMPORTED by src/template-consistency.test.ts.
+      // That file's skills-catalog block asks git two questions whose answers ARE
+      // its verdict — `ls-files '*SKILL.md'` and a `git grep` over the
+      // customer-facing surfaces — and both run against the REAL checkout, so a
+      // `GIT_DIR` or `GIT_INDEX_FILE` inherited from a hook would make them answer
+      // for a DIFFERENT repository while `cwd` still reads as this one. The test
+      // used to spell a hand-maintained ten-name allowlist inline; `gitFreeEnv()`
+      // replaces it, which is the #16644 convergence onto one spelling.
+      //
+      // FORCED rather than chosen, and the same shape as the `.d.mts` pair above:
+      // the import is a relative ES-module specifier vitest RESOLVES AND LOADS at
+      // run time, so the module is a live input to this package's verdict, and an
+      // undeclared escaping import is a red gate by design. Measured on the
+      // conversion commit before this line existed — the gate printed
+      // `scripts/git-env.mjs   (named in packages/create-objectstack/src/template-consistency.test.ts)`
+      // and exited 1.
+      'scripts/git-env.mjs',
       '.github/workflows/scaffold-e2e.yml',
       'packages/cli/src/commands/serve.ts',
       'scripts/gen-sdui-manifest.sh',
diff --git a/turbo.json b/turbo.json
index 1761f9f818e..4deb60b4fb3 100644
--- a/turbo.json
+++ b/turbo.json
@@ -502,6 +502,7 @@
         "$TURBO_ROOT$/content/**",
         "$TURBO_ROOT$/scripts/sync-template-versions.mjs",
         "$TURBO_ROOT$/scripts/invoked-as.mjs",
+        "$TURBO_ROOT$/scripts/git-env.mjs",
         "$TURBO_ROOT$/.github/workflows/scaffold-e2e.yml",
         "$TURBO_ROOT$/packages/cli/src/commands/serve.ts",
         "$TURBO_ROOT$/scripts/gen-sdui-manifest.sh",