Retry Pattern

ELI5 — The Vibe Check

Retry Pattern is trying something again when it fails, because sometimes failures are temporary (network hiccup, brief overload). But it's not just blindly retrying — smart retry uses exponential backoff (wait a bit, then a bit more) so you don't make an overloaded service worse.

Real Talk

The Retry pattern handles transient failures by automatically re-attempting a failed operation. Best practices include: maximum retry count, exponential backoff (increasing delays), jitter (randomized delays to avoid thundering herd), and idempotency requirements. Works alongside Circuit Breaker.

Show Me The Code

async function withRetry(fn, maxAttempts = 3) {
  for (let attempt = 1; attempt <= maxAttempts; attempt++) {
    try {
      return await fn();
    } catch (e) {
      if (attempt === maxAttempts) throw e;
      await sleep(2 ** attempt * 100); // exponential backoff
    }
  }
}

When You'll Hear This

"Add a retry with exponential backoff for the S3 upload." / "Retry three times before giving up and alerting the user."