diff --git a/.gitignore b/.gitignore
index d85de87..adbac73 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,8 @@ dist/
 *.tsbuildinfo
 .env
 .dev.vars
+# cc-taskrunner worktree protection
+C:*
+node_modules/
+.pnpm-store/
+__pycache__/
diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 100644
index 0000000..c9e109e
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1,12 @@
+## OSS Policy
+
+This is a **public infrastructure package** governed by the Stackbilt OSS Infrastructure Package Update Policy.
+
+Rules:
+1. **Additive only** — never remove or rename public API without a major version bump
+2. **No product logic** — framework patterns and generic utilities only. If a competitor could reconstruct Stackbilt product architecture from this code, it doesn't belong here.
+3. **Strict semver** — patch for fixes, minor for new features, major for breaking changes
+4. **Tests travel with code** — every public export must have test coverage
+5. **Validate at boundaries** — all external API responses validated before returning to consumers
+
+Full policy: `stackbilt_llc/policies/oss-infrastructure-update-policy.md`