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+# patches/
+
+`patch-package` patches for third-party dependencies. They are applied by the
+`postinstall` hook (`package.json`) and re-applied inside the Docker builder,
+which copies this directory before `npm ci` (`COPY ./patches ./patches`).
+
+Keep this directory tracked even when there is no patch: removing it breaks the
+Docker build, since the `COPY` above cannot resolve a path that does not exist.