Applied AI / Forward Deployed Engineer · Round-by-Round Playbook · Lesson 3 of 4
AI-assisted & debugging rounds
LLMs made classic take-homes and LeetCode trivially solvable, so loops split two ways: rounds where you're graded on driving AI well, and rounds engineered so AI can't help. Prep both — and always ask which mode you're in.
AI-assisted rounds (Sierra's 'AI-native interview', Meta's AI-enabled round, Canva, Ramp)
- The graded artifact is your judgment: prompt with intent (state the plan before asking), verify aloud (run/test everything the AI produces), visibly reject bad suggestions, and own the architecture yourself.
- Assume the AI chat transcript is reviewed — some platforms hand it to the interviewer. 'Paste task, paste output' reads as unskilled.
- Some interview AIs are deliberately weakened to test whether you catch their mistakes. Treat every suggestion like a junior engineer's PR.
Anti-AI rounds: debugging an unfamiliar codebase
- Format (Sierra, Scale, Palantir's re-engineering round): a multi-file agent/app plus a spec of intended behavior; find and fix several bugs, no AI tools, code must run.
- Method: read the spec first → trace one request end-to-end → diff intent vs. behavior → instrument (prints/logs) at the seam → fix, run to prove it, then hunt the next.
- Beware red herrings — ugly-but-working code is planted on purpose. Fix behavior, not style.
The meta-skillBoth formats test the same 2026 competency: can you judge code — yours, the AI's, or a stranger's — rather than merely produce it. Narrate your verification and you pass both.
◆ Lock it in
- AI-assisted rounds grade how you drive AI: intent-first prompts, verification aloud, visible rejection of bad output.
- Debugging rounds: spec → trace one request → diff intent vs behavior → instrument → fix and prove; ignore planted red herrings.
- Always ask what tools are allowed before every round.
Feynman drill — say it out loudExplain how you'd behave differently in an AI-allowed coding round vs. a no-AI debugging round — and what's common to both.
Step 1 rate your confidence · Step 2 pick your answer
In an AI-assisted coding round, the assistant produces a plausible-looking function. The strongest move is:
Step 1 — how sure are you?