CrackingWalnuts
Typically 12+ years (competency-gated, not tenure-gated). The bar shifts to multi-year bets, executive communication, and cross-org influence. Writing rounds and executive interviews carry more weight than coding. Story bank takes months to build.
Set technical direction for the org, shape multi-year bets, and multiply other engineers.
Salary is approximate market context, not a promise. It varies a lot by country, company, and year.
Can you actually do this?
If one makes you hesitate, that is the gap. Open it to go learn it.
60-90 min round. Write a memo arguing for a multi-year technical direction. Read by VPs and CTOs. The hardest round at Principal.
2-3 rounds. Multi-year bets, cross-org influence, growing Staff engineers, strategic failures. Story bank takes months.
Design a large system end to end with the deep trade-offs. Still a real round (Meta often runs two design rounds at E7). The architecture-at-scope round takes the same skill multi-org.
Multi-org, multi-year evolution. Design something that 10 teams build on top of. Bigger than single-system design.
1-2 rounds with a VP, Director, or CTO. Tests strategic communication, judgment, and altitude.
Common at Amazon, Microsoft. How would you split this team? Grow this org? Source senior talent?
Often skipped at Principal. If present, usually one practical round, not LeetCode.
If team is AI, infra, or research-focused. Deep domain expertise at multi-year timescale.
| Round | Tested? | Weight | What to expect |
|---|---|---|---|
| Technical Vision / RFC Writing | yes | high | 60-90 min round. Write a memo arguing for a multi-year technical direction. Read by VPs and CTOs. The hardest round at Principal. |
| Behavioral (Principal) | yes | high | 2-3 rounds. Multi-year bets, cross-org influence, growing Staff engineers, strategic failures. Story bank takes months. |
| System Design | yes | high | Design a large system end to end with the deep trade-offs. Still a real round (Meta often runs two design rounds at E7). The architecture-at-scope round takes the same skill multi-org. |
| Architecture at scope | yes | high | Multi-org, multi-year evolution. Design something that 10 teams build on top of. Bigger than single-system design. |
| Executive interview | yes | high | 1-2 rounds with a VP, Director, or CTO. Tests strategic communication, judgment, and altitude. |
| Org Design / Hiring | sometimes | high | Common at Amazon, Microsoft. How would you split this team? Grow this org? Source senior talent? |
| Coding | sometimes | low | Often skipped at Principal. If present, usually one practical round, not LeetCode. |
| Domain Round | sometimes | high | If team is AI, infra, or research-focused. Deep domain expertise at multi-year timescale. |
Principal rounds test altitude, judgment, and writing. Most candidates over-prepare technical depth and under-prepare communication and judgment.
Write a 4-page memo arguing a multi-year direction. Practice this 5-10 times. The single most differentiating prep area.
Multi-year bets, cross-org influence, executive moments, growing Staff engineers, strategic failures.
How would you structure this org for a multi-year goal? When to split vs merge teams? When to hire vs reorg?
Reading, writing, and critiquing ADRs at company-altitude. Multi-year evolution paths.
Influence without authority, technical strategy, managing through other Staff engineers.
Org-level incident response, blameless postmortem culture, building reliability programs.
Multi-year cost trajectories, DORA at scale, picking what to measure across an org.
AI labs and AI-adjacent loops require deep architectural fluency: LLM fundamentals, inference, training, evals, safety.
Platform, infra, and DevEx orgs expect fluency in internal developer platforms, golden paths, and platform-as-a-product trade-offs at multi-year scope.
Data and infra orgs expect architectural fluency in storage engines, consistency, and replication trade-offs: B-tree vs LSM, MVCC, isolation levels, at multi-system scope.
Principal loops still run system-design rounds (Meta often runs two at E7). Multi-system, multi-org architecture builds on solid HLD fundamentals, so keep them sharp.
Optimization tricks for LeetCode. Not on the bar.
If your story is one team for two months, it's a Senior story, not Principal.
Multi-year arcs are the bar. Quarter-scale stories will undersell you.
Reciting the Spotify architecture is Senior. Principal is about strategic bets and trade-offs at multi-year scale.
Naming senior leaders you've worked with reads as insecure. Show altitude through what you decided, not who you stood next to.
Writing and behavioral carry the most weight at Principal. The Staff+ Interview Prep section is the single highest-leverage study area.
RFC writing, technical strategy, organizational design. The signature Principal rounds. Practice 5-10 RFCs.
Multi-year stories with executive context. Story bank takes weeks. Practice telling each in 5-8 minutes.
Read 30+ public ADRs at multi-year scope. Practice writing them in 60 minutes.
Reorg patterns, team topologies, hiring strategy. Common executive-interview territory.
Influence without authority. Managing through other Staff engineers. Communication at altitude.
Org-level incident response. Have 2 specific stories where you led a major incident response.
Multi-year cost trajectories, DORA at scale. Common topic in executive rounds.
Principal loops still run system-design rounds (Meta often runs two at E7). You likely have the fundamentals; refresh them so the multi-system architecture round is a step up, not a scramble.
Assumes 8-10 hours per week. Principal prep is the longest because the writing rounds and story bank both take real time to do well.
Principal loops differ widely. Click through for the full breakdown of each company's writing rounds, executive panels, and required artifacts.
7-8 rounds: 2 system design (one is multi-system architecture), 2 behavioral, 1 writing (memo), 1 executive (Director/VP), 1 hiring committee.
7+ rounds: architecture, leadership, hiring committee, executive (Director+), strategic communication. Cross-functional scope expected.
6-7 rounds, one a Bar Raiser. Heavy on Leadership Principles, especially the 'big ones' (Customer Obsession, Think Big, Earn Trust). Writing exercise required.
Practical architecture, multi-system design, writing memo, executive (VP), Operating Principles behavioral. Written rounds heavier than other companies.
6-8 rounds: technical strategy, architecture, behavioral (leadership and impact signal), VP/CTO round. Mature org-level expectations.
Heavy on technical strategy in AI infrastructure, safety-mindedness, judgment under uncertainty about capabilities and risks.
Targeting a company not listed? The bar is the same across big tech. Pick the closest example above, or browse all companies.