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- Retry with Exponential BackoffTools time out and APIs rate-limit — a production agent retries without hammering. Exponential backoff waits longer after each failure (1s, 2s, 4s, 8s…) up to a cap. Compute the delay schedule: delay[i] = min(cap, base·2ⁱ). Solve it in Python or TypeScript.Read →
- Verify a Webhook SignatureEvery real integration sends signed webhooks — and every FDE has to verify them. Recompute the signature over the payload, compare in constant time, and reject stale events to stop replay attacks. Solve it in Python or TypeScript, with hidden tests.Read →
- Idempotency Key HandlerNetworks retry. A webhook fires twice; a payment is re-sent after a timeout. Without idempotency you double-charge or double-write. The fix: dedupe by a client-supplied key and always return the first result. Solve it in Python or TypeScript, with hidden tests.Read →
- CSV → Schema MapperEvery customer hands you a messy export. Before it flows into your system, each row must be coerced to a schema — strings to ints, "true" to booleans — and the rows that don’t fit quarantined, not silently dropped. Solve it in Python or TypeScript, with hidden tests.Read →
- PII RedactorBefore customer data touches a log line — or a third-party LLM — the personal bits have to go. Mask emails, SSNs, credit cards, and phone numbers with pattern matching, leaving the rest readable. Solve it in Python or TypeScript, with hidden tests.Read →
- Config ValidatorHalf of "it doesn’t work at the customer" is a bad config — a missing key, a string where an int belongs, an env that isn’t allowed. Validate it up front and fail loudly with a clear list instead of crashing three layers deep. Solve it in Python or TypeScript, with hidden tests.Read →