Exponential backoff with jitter for retries

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                  export async function retry<T>(fn: () => Promise<T>, opts: { attempts: number; baseMs: number; maxMs: number }) {
  let lastError: unknown;
  for (let i = 0; i < opts.attempts; i++) {
    try {
      return await fn();
    } catch (e) {
      lastError = e;
      const exp = Math.min(opts.maxMs, opts.baseMs * 2 ** i);
      const jitter = Math.random() * exp * 0.25;
      await new Promise((r) => setTimeout(r, exp + jitter));
    }
  }
  throw lastError;
}

Immediate retries are a great way to stampede a struggling dependency. I use exponential backoff with jitter so retries spread out naturally and don’t synchronize across instances, and I cap the maximum delay so worst-case latency doesn’t become unbounded. The practical detail is deciding what to retry: only idempotent operations and only on transient errors (timeouts, 5xx, rate limits, 429). When errors are permanent (4xx that aren’t 429), I fail fast. This tiny utility gets reused everywhere—HTTP clients, queue consumers, even UI polling—and it improves reliability without changing business logic.

Mateo Rodriguez

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Exponential backoff with jitter for retries

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