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9 articles
Backend Engineering
Which comparison function each precondition mandates, the normative evaluation order, the Authorization back door in RFC 9111, why Vary silently fails at the CDN, and RFC 9875 Cache Groups.
Backend Engineering
The IETF Idempotency-Key draft expired in April 2026 and never reached the IANA registry. What to build instead: key scoping, atomic claims, response snapshots, and TTL.
Backend Engineering
How to emit the IETF RateLimit and RateLimit-Policy fields (still an Internet-Draft, not an RFC), choosing between fixed windows and token buckets, why INCR plus EXPIRE leaks keys that never expire, and pairing 429 with Retry-After correctly.
Backend Engineering
Secure webhooks with raw-body HMAC, constant-time comparison, signed timestamps, delivery deduplication, business idempotency, durable inboxes, and key rotation.
Backend Engineering
Build a recoverable MongoDB Change Streams consumer with opaque resume tokens, idempotent effects, CAS checkpoints, backpressure, backfills, and reconciliation.
Backend Engineering
Instrument FastAPI with OpenTelemetry, export OTLP through a Collector, control sampling and sensitive data, preserve background-task context, and verify the trace pipeline before production rollout.
Backend Engineering
Why to target Redis 8.6.5, how XADD IDMP and IDMPAUTO idempotent production works, sizing IDMP-DURATION and IDMP-MAXSIZE, LRM eviction, HOTKEYS, and a staged upgrade sequence with rollback gates.
Backend Engineering
Choose between FastAPI BackgroundTasks, Celery, and durable workflows using persistence, retry, idempotency, outbox, HTTP 202, state, scheduling, and recovery requirements.
Backend Engineering
Build recoverable FastAPI SSE streams with stable event IDs, Last-Event-ID, Nginx buffering controls, heartbeats, backpressure, authorization, and production tests.
