Harden fetch retry client
Hard JavaScript arena: fetch, AbortController, retries, backoff, and error envelopes
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Missing prerequisites: javascript-easy-fetch-retry
A frontend calls a flaky endpoint and needs predictable user-facing errors. You are working inside a modern JavaScript application, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply fetch, AbortController, retries, backoff, and error envelopes in a modern JavaScript application while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates fetch, AbortController, retries, backoff, and error envelopes
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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