Cloud & DevOps
A dependency being down shouldn't reach your users as a stack trace. Five resilience policies — retry, backoff, circuit breaker, timeout and fallback — and, more importantly, when each one makes things worse.
System Architecture
Every queue worth using promises at-least-once delivery, which is a polite way of saying your handler will run twice. Here is the set of patterns — idempotency keys, the outbox, dead-letter queues and sagas — that make that a non-event.
Backend Engineering
The compiler rewrites your async method into a state machine. Once you can picture that machine, ValueTask, ConfigureAwait and the classic WaitAll deadlock all stop being trivia and start being obvious.