StaffSignal

The Missing Manual for Staff Engineers.

Most senior engineers fail Staff interviews for one reason: they solve the problem — but don't demonstrate Staff-level signal. StaffSignal makes evaluation criteria explicit.

Built for engineers targeting L6–L7 at MAANG. Not for entry-level prep.

Staff Playbooks

Deep, opinionated guides to what evaluators actually look for. Not blog posts — operating manuals.

Distributed Caching

  • L5 vs L6 expectation breakdown
  • When caching is necessary vs premature
  • Who owns correctness when cache and DB diverge?
  • Failure modes evaluators specifically look for
Read playbook →

Message Queues & Event-Driven Systems

  • Throughput vs reliability tradeoffs
  • Delivery guarantees explained without hand-waving
  • The "exactly once" myth and what to say instead
  • What Staff candidates articulate that seniors don't
Read playbook →

Rate Limiting & Traffic Control

  • Algorithm comparisons (token bucket vs leaky bucket vs sliding window)
  • Multi-region coordination implications
  • Abuse handling vs product constraint tension
  • When you're over-designing and how evaluators spot it
Read playbook →

What Changes Between Senior and Staff?

Staff interviews are not about better diagrams. They're about broader accountability.

DimensionSenior (L5)Staff (L6)
ScopeOwns a component or serviceOwns a cross-team technical surface
TradeoffsEvaluates local optionsFrames org-level impact and cost
RiskIdentifies and manages riskAnticipates failure modes before they're raised
Design communicationExplains what they builtFrames the problem, aligns stakeholders, then builds
Ownership signal"I implemented X""I identified the gap, proposed the approach, and drove adoption"

Every StaffSignal playbook includes L5 vs L6 contrast tables for the specific topic. This is the level calibration that other platforms skip.

Built for

  • Engineers targeting Staff (L6) or Senior Staff (L7) roles
  • Engineers who've been told "not enough scope" or "didn't demonstrate ownership" in debrief
  • Senior engineers (L5) who want to understand what the next level actually requires
  • Engineers who can already design systems but need evaluation calibration

Not for

  • Entry-level interview prep
  • LeetCode speed grinding
  • Template memorization ("just draw the boxes")
  • Anyone looking for a generic "get hired at Big Tech" course

Why This Exists

Built by an engineer who has evaluated design rounds, sat in debrief rooms, and watched strong candidates fail for non-obvious reasons. StaffSignal exists because the criteria that determine Staff-level hiring decisions are real, consistent, and documentable — but almost never written down.

Start with the playbooks.

Read one before your next interview. The evaluation criteria don't change — but your awareness of them will.