Infrastructure, pipelines, Kubernetes, and the reliability and incident-response judgement that defines the SRE round.
Treat it as a process gap, not a grudge. Find out where and when decisions are made, get your team's constraints in front of the deciders before the meeting through short written proposals with a comment window both time zones can reach, and escalate a specific costly decision, not the people who made it.
In a transfer, atomicity means the debit and credit commit together or not at all, consistency means declared constraints such as a non-negative balance still hold, isolation stops concurrent transactions seeing or overwriting each other's half-done work, and durability means a confirmed commit survives a crash.
Evaluate feature flags in an SDK from a cached ruleset, assign users by hashing a per-experiment salt with the user id so assignment is sticky, log exposure where the arms first diverge, gate readouts on an automated SRM check, and make the kill switch a top-precedence rule that works with the control plane down.
Debugging an unfamiliar codebase starts by running the failing test, then reading it as the rule and tracing its call path to the code that computes the wrong value. Let the size of the error narrow the cause, ask the assistant to locate and explain rather than patch, and prove the fix with a test that failed before.
A notification system at 50 million a day is sized by bursts and provider limits, not its average of about 580 a second. Accept with an idempotency key, apply preferences once, fan out to per-channel queues with transactional and bulk lanes, rate-limit each provider, and never fail over blindly on a timeout.
Deadlock needs all four Coffman conditions at once: mutual exclusion, hold and wait, no preemption and circular wait. Breaking any one prevents it, and the practical choice is usually circular wait, by making every thread take locks in one global order.