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+# JSON File Writing Must Be Atomic
+
+- You MUST use `safeWriteJson(filePath: string, data: any): Promise<void>` from `src/utils/safeWriteJson.ts` instead of `JSON.stringify` with file-write operations
+- `safeWriteJson` will create parent directories if necessary, so do not call `mkdir` prior to `safeWriteJson`
+- `safeWriteJson` prevents data corruption via atomic writes with locking and streams the write to minimize memory footprint
+- Test files are exempt from this rule