Node.js Code Review Patterns

Stack-specific rules loaded by dh:code-reviewer when package.json and *.js/*.mjs files are detected (without TypeScript).

Synchronous I/O in Request Path

• fs.readFileSync, fs.writeFileSync, execSync, spawnSync in any function called during request handling are blocking findings
• Synchronous I/O blocks the event loop and degrades all concurrent requests
• All file system operations in server code must use the async variants or fs/promises

// WRONG: blocks event loop
app.get("/config", (req, res) => {
  const config = fs.readFileSync("./config.json", "utf8");
  res.json(JSON.parse(config));
});