diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..394a1a5
--- /dev/null
+++ b/.gitignore
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+# Coding-agent review-findings dirs. Automated review tooling writes these at
+# the repo root of a working tree. They hold internal run identifiers and raw
+# review commentary, so a broad `git add -A` must never sweep them into a PR.
+.architect/
+.reviewer/
+
+# macOS
+.DS_Store
+
+# Node
+node_modules/