Senior → staff calibration
The staff signal is scope: you reason about failure, capacity, and cost from the first minute. This path tightens the framings interviewers listen for.
For: Strong seniors pursuing staff-level rounds
After this path
Sound like an engineer who has shipped systems at scale, not one who has read about them.
- 1Skill
Capacity estimation (back-of-envelope)
Deriving QPS, storage, bandwidth, memory from user-facing numbers.
Why this, here: The staff signal is the numeric reasoning in the first 3 minutes.
- 2Skill
Failure mode analysis
What fails, blast radius, graceful degradation, retries, circuit breakers.
Why this, here: Pre-empt the "what fails" probe by raising it yourself.
Checkpoint
Staff framing drill: volunteer a failure mode and its mitigation before the interviewer asks. Say the sentence now, out loud, for the last system you worked on. If it sounds rehearsed, good — it should.
- 3Pattern
Multi-region active-passive / active-active
Geographic distribution for latency, DR, and compliance. Active-passive is operationally sane; active-active is a conflict-resolution project.
Why this, here: DR, latency, residency — staff rounds always touch this.
- 4Deep dive
Consensus and leader election
Raft-style coordination, leases, fencing tokens, quorum, and exactly-one leadership.
Why this, here: Names the real primitive instead of "we have a leader somehow".
- 5Skill
Observability & operations
Metrics, logs, traces, SLOs, alerting on symptoms not causes.
Why this, here: SLOs and error budgets are a staff-level vocabulary.
Checkpoint
State an SLO for a system you own (availability or latency), the error budget math behind it, and what you’d cut first when the budget is exhausted. Vague answers here get filtered at staff-plus.
- 6Deep dive
CDC and eventing
Outbox, change-data-capture, derived views, dual-write avoidance, and replay safety.
Why this, here: How mature systems avoid dual writes. Outbox + CDC is table stakes.