Elite AI-Lab SWE Interview Program
An executable training program for elite AI-lab software-engineering loops — OpenAI, Anthropic, DeepMind, Scale, Cursor, xAI, Databricks, Netflix, Stripe. Not a reading list: source code, gated drills, scored rubrics, and a progress ledger you run day by day.
Target: senior / staff, IC track. Budget: 22 h/week × 26 weeks ≈ 570 hours.
Table of Contents
- Current Phase
- Start Here
- What This Is
- The Loop This Is Built Against
- Repository Layout
- The Runnable Tools
- The Seven Tracks
- Beyond the Ask
- Operating Rules
- Honest Status
- References
Current Phase
Phase 1 — Calibrate. Week 0.
Phase 0 research is complete. The diagnostic battery is built and runnable.
PLAN.md is deliberately locked until you report diagnostic scores — writing
it now would mean guessing your level, and a plan optimized for a person who does not exist is
worse than no plan.
Your next action: take the 3-hour baseline diagnostic.
Live status in STATE.md.
Start Here
| Step | Do this | Time |
|---|---|---|
| 1 | Read research/findings.md — what is confirmed, what is reported, what is inferred | 20 min |
| 2 | Take the baseline diagnostic, cold, timed, no tools | 3h 05m |
| 3 | Score it against RUBRIC.md; record in scores/ | 45 min |
| 4 | Report the numbers. PLAN.md unlocks | — |
| 5 | Begin week 1 | — |
Do not read diagnostics/ANSWER-KEY.md or any solution.py
before step 3. A contaminated baseline produces a plan for the wrong person.
The study guides
The actual teaching material. Each is self-contained — every concept from first principles, full implementations, worked scenarios, and the follow-up questions with answers. You should not need to leave these files to understand them.
| Guide | What it teaches | Verified |
|---|---|---|
| Track A — The Ten Patterns | MVCC & predecessor queries · delta logs · intrusive lists · rate limiting · heap scheduling · streaming parsers · dependency graphs · WAL · Bloom filters · backpressure. Complete implementations, not sketches | 63 behavioural checks green |
| Track A — The Follow-Up Bank | 150 questions asked after your code works, with mechanism-level answers — complexity probes · the 100× question · "why not X" · "now make it concurrent" · "how would you test this". The coding round is decided here, not by the tests passing | measured on 3.13 |
| Track B — The CPython Runtime | Object model · iterators & generators · the event loop built from scratch · the GIL · memory & allocators · the data model | measured, live interpreter |
| Track B — Quiz Bank | 150 questions with mechanism-level answers | spot-checked live |
| Track C — Distributed Primitives | Little's law & the utilization knee · failure taxonomy · clocks & HLCs · leases and fencing · quorums · Raft at usable depth · consistency models · partitioning · delivery semantics · load control · CRDTs | — |
| Track C — The Twelve Worked Designs | All twelve designs worked end to end — nine sections each, then attacked by a hostile staff interviewer, then revised. 72 critiques, 72 revisions, plus the cross-cutting pattern map and the defect taxonomy across all of them | — |
| Track D — Inference Infrastructure | The KV cache · the roofline derivation · memory budgets · continuous batching, PagedAttention, chunked prefill · prefix caching · speculative decoding · parallelism · autoscaling · a complete worked "design ChatGPT" at both altitudes | 24 arithmetic claims verified |
| Track D — The Eight ML-Infrastructure Designs | All eight worked end to end — LLM API platform · KV cache tier · GPU cluster scheduler · pretraining data pipeline · eval harness · RAG serving · LoRA serving · training fault tolerance. 48 critiques, 48 revisions, plus the eight calculations that decide them | every number script-checked |
| Track E — The 48 Hours and the Interrogation | The hour-by-hour playbook, the webhook system specified with its seven logged decisions, and the deep-dive interrogation with 40 questions and full model answers | — |
| Track F — Behavioral, Worked | All twelve story categories with model answers at staff density, the probe playbook, and the forward-looking answers written in full | — |
| Track G — Driving an Agent | The method in eight steps, a fully worked 60-minute transcript with scoring commentary, and five diffs to accept or reject | — |
| Track G — The Diff Bank | 30 agent-produced diffs to accept, reject or revise in 90 seconds each — the six-pass review, the ranked taxonomy of what agents get wrong, and three that look wrong and are right | measured on 3.13 |
The two reference documents
Not teaching material — retrieval material. Read the guides once; read these the morning of.
| Document | What it is |
|---|---|
| CHEAT SHEET | Everything above compressed to what fits in working memory: the loop, the coding query-shape table, the version-dependent Python facts, the distributed arithmetic and fencing rules, the inference formulas and numbers, the take-home playbook, the behavioural frame, and the verbatim scripts to say out loud |
| Glossary | Every term used anywhere in the program, defined in one line, with a pointer to where it is taught. Use it when a guide assumes something you have not met yet |
What This Is
Most interview prep is a list of things to read. Reading does not make you faster under a timer, does not teach you to defend a design under attack, and does not produce a story bank.
So this is built as an engineering project instead:
- A stage-gated coding harness that refuses to show you the next requirement until your code passes the current one — reproducing the reported onsite format's actual constraint.
- A diagnostic battery with a scoring rubric that maps to a starting level per track, so the plan is built from measurement rather than assumption.
- Runnable experiments for every claim about the Python runtime. No prose assertions.
- Back-of-envelope calculators so the arithmetic you do out loud in a design round is reflex.
- GPU memory and roofline math you can derive on a whiteboard.
- A spaced-repetition queue that resurfaces everything you got wrong at 1, 3, 7, 21 days.
- Weekly scored mocks on a hire-bar scale, with the level stated plainly.
Nothing is marked complete because you read it. Completion requires a passed drill, a working artifact, or a scored mock.
The Loop This Is Built Against
Reconstructed from one candidate's account, then corroborated where possible. Full epistemic
labelling in research/findings.md; the 41-row fidelity checklist in
research/source-report.md.
| Stage | Reported shape | Track |
|---|---|---|
| Recruiter screen | Background + "where is AI headed"; read the charter first | F |
| Technical screen | Two 60-min rounds, same day: coding (versioned KV store) + design (fault-tolerant job scheduler) | A, C |
| Take-home | 48h, "build something real" — e.g. distributed webhook delivery with retries and DLQ | E |
| Deep dive | Line-by-line walk of your code, from a question list written after reading it | E |
| Onsite ×4 | Progressive coding (token-stream differ with rollback) · systems coding + Python internals · design ChatGPT · behavioral | A, B, D, F |
| Agentic round | Beta fifth round: oversized task in a real codebase, driven through an AI agent | G |
A caution that shapes the whole program. The originating source is a single unverified candidate account. The loop varies by team, level, and quarter. So roughly a quarter of the material is deliberately off-report, the onsite is prepared as six components rather than four, and nothing here is asserted to an interviewer as fact about their process. See the anti-narrowing clause.
Repository Layout
README.md this file — entry point and current phase
PLAN.md the 26-week program (locked pending diagnostic)
STATE.md progress ledger; updated every session
research/ findings, fidelity checklist, company brief
diagnostics/ baseline battery, answer key, rubric, scores
tracks/
coding/ Track A + the progressive harness (15 problems)
python-internals/ Track B + 5 runnable experiment scripts
systems-design/ Track C + envelope calculators + 12 designs
ml-infra/ Track D + gpu_math.py
behavioral/ Track F — story bank, probes, forward-looking
agentic/ Track G — agent-driving method and tasks
projects/ the real builds — take-homes, portfolio, essay
mocks/ weekly scored mocks, transcripts, hire-bar scale
review/ spaced repetition queue + failure log
The Runnable Tools
Everything here works today.
# Track A — the stage-gated harness
cd tracks/coding/harness
./progressive.py list
./progressive.py start token-stream-differ # prints gate 1 only
./progressive.py test token-stream-differ # unlocks gate 2 on pass
./progressive.py chart # time-to-first-gate trend
# Track B — proof, not prose
cd tracks/python-internals/experiments
python3 exp01_generators.py exp02_async.py # (run individually)
python3 exp03_gil.py # measures a real lost-update race
python3 exp04_memory.py # __slots__, memoryview, tracemalloc
python3 exp05_datamodel.py # descriptors, MRO, __getattr__
# Track C — the arithmetic you say out loud
cd tracks/systems-design/calculators
python3 envelope.py qps --rps 50000 --ms 8
python3 envelope.py retry --rps 10000 --fail 0.3
python3 envelope.py latencies
# Track D — the memory and roofline math
cd tracks/ml-infra
python3 gpu_math.py --model llama-70b --gpu h100 --gpus 4
# review — spaced repetition
cd review
python3 review.py add "..." --confident-wrong
python3 review.py drill
# the diagnostic
cd diagnostics/d1-coding
cp starter.py attempt.py && python3 test_diagnostic.py attempt.py
The Seven Tracks
| Track | Tests | Baseline share |
|---|---|---|
| A — Coding under time pressure | Screen A; onsite Coding 1 & 2 | 25% |
| B — Python internals | Coding 2's follow-ups | 12% |
| C — Distributed systems design | Screen B | 15% |
| D — ML & inference infra | "Design ChatGPT" | 20% |
| E — Take-home & deep dive | The 48h build and its defence | 12% |
| F — Behavioral at staff altitude | Recruiter + onsite behavioral | 10% |
| G — Agentic coding | The beta fifth round | 6% |
Shares are the baseline. They are re-derived from your diagnostic levels and rebalanced at each of the six monthly re-tests.
Beyond the Ask
The differentiators, built into the schedule rather than left as good intentions:
| Artifact | What it is | When |
|---|---|---|
| Portfolio project | A deep public-quality build in search/retrieval or serving, with a benchmark and honest measured numbers | wk 10–20 |
| Technical opinion | An essay with a falsifiable claim and a stated falsifier — the real answer to "where is AI headed" | wk 6–12 |
| Reading and rebuttal | Close reading of their published engineering work, with a specific question about a design choice | wk 1, ongoing |
| Numbers sheet | Latency, throughput, cost and hardware figures, each verified and attributed | wk 22 |
| Failure log | Every miss, the actual gap behind it, and the fix — with a recurrence check | continuous |
Operating Rules
Applied without exception:
- Reading never completes anything. Passed drill, working artifact, or scored mock.
STATE.mdupdated every session. The next session starts cold and reads only that file.- Weekly scored mock, on the hire-bar scale, with the level stated plainly — including no hire.
- Score down when unsure. A generous rubric is the one thing that guarantees failure.
- Spaced repetition at 1, 3, 7, 21 days. Wrong at any interval resets to 1.
- Every performance claim has a script that demonstrates it.
- Inference is labelled as inference. Nothing speculative about anyone's process is presented as fact, and none of it is ever said to an interviewer.
- Commit at every milestone, with a real message.
Honest Status
What exists today versus what is scheduled — so nothing here overstates itself.
| Component | Status |
|---|---|
| Study guides — Tracks A–G + the 150-question quiz bank | ✅ complete |
| Worked artifacts — design-ChatGPT answer, 40-question deep-dive interrogation, 60-min agent transcript, twelve behavioural stories | ✅ complete |
| Phase 0 research, 41-row fidelity checklist, company brief | ✅ complete |
| Baseline diagnostic: 4 parts, answer key, rubric, scoring template | ✅ complete and runnable |
| Progressive harness CLI (gating, timing, chart) | ✅ complete |
| Harness problems: 15 problems, 60 automated gates | ✅ 60/60 green — every problem, every gate |
| Track B runnable experiments | ✅ 5 scripts, all verified |
| Track C envelope calculators | ✅ complete |
Track D gpu_math.py | ✅ complete |
review.py spaced-repetition queue | ✅ complete |
| Track READMEs: inventories, drills, failure modes, rubrics | ✅ all 7 |
Worked designs d01–d12 (distributed) — each with 6 hostile critiques + 6 revisions | ✅ all twelve complete — attempt each yourself first; they are the answer key, not a substitute |
Worked designs m01–m08 (ML infrastructure) — same shape, 48 critiques + 48 revisions | ✅ all eight complete, every number script-verified |
| CHEAT SHEET + Glossary | ✅ complete |
| Story bank | ⏳ requires your raw material; will not be invented |
| Projects | ⏳ weeks 8, 16, 10–20 |
PLAN.md week-by-week | 🔒 locked pending diagnostic |
Every runnable artifact is verified: python3 tracks/coding/harness/runtests.py runs all 60
gates in about six seconds. Remaining scheduled work is tracked in STATE.md.
References
research/findings.md— Phase 0, with confirmed / reported / inference labels and full sourcesresearch/source-report.md— the 41-row fidelity checklist and coverage auditresearch/company-brief.md— charter digest, talking points, the three questions you askdiagnostics/README.md— the battery and how to take itPLAN.md— the 26-week programSTATE.md— where you are right now- Related tracks in this hub: llm-inference-engineer · Senior AI Engineer · agentic-engineer · pretraining-lead