Skip to content

Series

Progress

AI Engineer

0 / 10

Product Builder

0 / 10

Daily Drills (latest 14)

AI Engineer Interview Daily — 2026-09-05: Paper Reading

Paper reading rounds don't test whether you memorized a paper's conclusion — they test whether you can break down an unfamiliar paper's problem, method, and limitations in 15-20 minutes and ask a meaningful follow-up question. Today's paper introduces invalidation contracts: attaching version stamps and cacheability hints to cached LLM-agent error-recovery suggestions, so that when server-side data drifts, the client can evict exactly the stale entries at row-level granularity instead of discarding everything or re-deriving from scratch every time. The paper's core insight is decomposing 'did this caching mechanism actually save money' into two independent variables — validity (whether the cached content is still correct, determined purely by protocol design) and compliance (whether the planner model actually adopts the suggestion on the first try, which is model-dependent: the same wire bytes get 100% first-try compliance on Claude Haiku 4.5 but can drop below 11% on Claude Sonnet 5). That decomposition itself is great interview material — it demonstrates how to split a vague performance question into two separately measurable, separately attributable factors.

Product Builder Interview Daily — 2026-09-05: Technical PM

Technical PM interviews don't test whether you can design systems — they test whether you can discuss trade-offs with engineers in the same language. Today we use the RFC process (Draft-Review-Decision-Implementation) to practice narrowing a technical discussion, and the Architecture Decision Record (Context-Decision-Consequences-Alternatives) to practice writing up a technical trade-off clearly and traceably — practicing a real Stripe technical-round question from Exponent: design a ledger service.

AI Engineer Interview Daily — 2026-09-04: Coding

ML coding interviews don't test whether you've memorized LeetCode templates — they test whether you can hand-write building blocks in NumPy (linear layers, residual connections, layer norm, causal self-attention) and read someone else's training/inference loop well enough to find the bug. Today covers four concepts: the real test in ML coding interviews is hand-implementation, not memorized answers; BPE tokenizer's core logic is 'count frequencies, merge iteratively, encode using the exact same merge order learned during training' — get the order wrong and encode no longer matches decode; batch inference trade-offs throughput against latency and has to handle padding waste across variable-length sequences; and the test for whether to vectorize a loop in NumPy is whether it has cross-element dependencies. The practice problem is a real technical-screen question from Glean — implementing a BPE tokenizer end to end, from training to encode/decode.

Product Builder Interview Daily — 2026-09-04: Growth & Experimentation

The gap most Growth interview answers miss isn't a lack of ideas — it's forgetting that in a two-sided marketplace, growth only counts if both sides (Guests and Hosts) grow together. Today we use HubSpot's Growth Flywheel (Attract-Engage-Delight) to map the compounding structure of growth, then use Nir Eyal's Hook Model (Trigger-Action-Reward-Investment) to design a habit loop that brings users back without being pushed — practicing a real 2026 Airbnb interview question from Exponent: How would you 3x Airbnb's growth?

AI Engineer Interview Daily — 2026-09-03: LLM & Agent Engineering

LLM & Agent Engineering interviews don't test whether you can wire up LangChain — they test whether you can turn a vague 'something's broken' into a set of testable sub-hypotheses. Today covers four high-frequency concepts: why RAG's 'retrieval is right but the answer is wrong' gap needs retrieval and generation evaluated as two separate systems; why a bigger agent context window doesn't fix quality decay, because the real problem is context pollution (noise diluting attention) rather than too few tokens; the decision logic between RAG and fine-tuning — 'RAG owns knowledge, fine-tuning owns behavior'; and why LLM-as-judge carries consistency and self-preference bias and can't stand alone as the only metric. The practice problem is a common enterprise scenario question — retrieval accuracy is 90% but answer accuracy is only 60%, how do you diagnose it — walking through how to turn a vague symptom into verifiable hypotheses.

Product Builder Interview Daily — 2026-09-03: AI Product Design

AI product questions rarely fail because you can't paint a vision — they fail because you can't say how the model breaks, and what happens to the user when it does. Meta rewrote its PM interview loop for the first time in five years this year, adding a round called 'Product Sense with AI' that has candidates solve a product problem alongside AI in real time — testing exactly this. Today we use the 'map failure modes → define minimum viable quality (MVQ) → design guardrails' framework from Marily Nika, a former Google/Meta AI PM, to break down a real case: a Slack-summary assistant that turned an undecided discussion into a committed decision and assigned an owner who never agreed to anything. The case study looks at how GitHub Copilot's ghost text drives the cost of ignoring a suggestion toward zero, letting users calibrate which suggestions to trust across hundreds of interactions.

AI Engineer Interview Daily — 2026-09-02: ML System Design

ML System Design interviews don't test whether you can draw an architecture diagram — they test whether you can articulate the trade-offs at every layer. Today covers four high-frequency topics: how a feature store guarantees training/serving consistency, how to sequence deployment strategies with automated rollback triggers, why monitoring needs to split into system/data/model layers with PSI/KS tests for drift, and how to budget latency for online inference down to the millisecond. The practice problem is 'design a real-time e-commerce recommendation service,' walking through requirement clarification, scale estimation, feature store design, and deployment strategy end to end.

Product Builder Interview Daily — 2026-09-02: Strategy & Execution

Strategy questions rarely fail because you can't size a market — they fail because you conflate 'this market is worth pursuing' with 'we can actually win it.' Exponent's latest Google Product Strategy Interview Guide includes a classic market-entry question: should Google enter the online furniture retail market. Today we break it down with Porter's Five Forces and TAM-SAM-SOM, using Zoom's fight into a market already locked down by Cisco WebEx and Skype as the case study — strategy questions ultimately hinge not on market size, but on whether you have an edge competitors can't copy.

AI Engineer Interview Daily — 2026-09-01: Deep Learning & NLP

Deep Learning & NLP interviews don't test whether you can draw a transformer diagram — they test whether you understand what each design decision trades away. Today covers four high-frequency topics: how self-attention computes and what KV cache saves, the vocab-size trade-off in tokenization, the senior-candidate detail that 'an embedding is a vector-space contract, and matching dimensions doesn't mean compatible,' and how to choose between fine-tuning and prompting while guarding against catastrophic forgetting. The practice problem is Scale AI's 'design an embedding and classification API,' walking through version compatibility, partial failure, and multi-tenant isolation end to end.

Product Builder Interview Daily — 2026-09-01: Metrics & Analytics

Metrics questions rarely fail because you picked the wrong metric — they fail because you can't say why that metric represents user value, or you mistake correlation for causation. Exponent's latest 2026 real-interview roundup includes a Meta-style execution question: comments are up but watch time is down, what do you do. Today we break it down with a metric tree, using Facebook's famous '7 friends in 10 days' north star metric as the case study — it found Facebook's growth lever, and it also became one of Silicon Valley's most-cited correlation-causation traps.

AI Engineer Interview Daily — 2026-08-31: ML Fundamentals

ML fundamentals interviews test whether you can diagnose the gap between 'the metric looks great' and 'production is on fire.' Today covers four high-frequency topics: why AUC-ROC inflates under heavy class imbalance, why cross-entropy beats MSE for classification (it comes down to vanishing gradients), whether bagging or boosting fixes variance versus bias, and the common misconception that multicollinearity hurts prediction — it only hurts interpretability.

Product Builder Interview Daily — 2026-08-31: Product Sense

Product Sense questions rarely fail because you can't think of a feature — they fail because you can't say why that feature, and not another. Exponent's latest 2026 real-interview roundup notes an Adobe candidate was asked to 'design a feature for LinkedIn,' and the strongest answers all committed to one user segment early instead of listing ten ideas. Today we pair CIRCLES with a root-cause layer to work through that question, using Airbnb's early 'photograph hosts' listings by hand' move as the case study.

AI Engineer Interview Daily — 2026-08-30: Weekly Review & Behavioral

A behavioral interview isn't testing whether you have a story — it's testing whether you can turn a technical incident into a narrative with a clear situation, concrete actions, and quantified results in 90 seconds. Today walks through a full STAR answer for the AI Engineer classic — 'a deployed model's performance suddenly collapsed, how did you fix it under cross-team pressure' — and reviews what got practiced this week across the five topics from ML Fundamentals through Paper Reading.

Product Builder Interview Daily — 2026-08-30: Behavioral & Weekly Review

A Behavioral interview isn't testing whether you have a great story — it's testing whether the committee can answer 'will this person get better over time' after hearing it. Today practices an influencing-without-authority scenario using the STAR-R framework (Situation-Task-Action-Result-Reflection), built around a real Amazon L5 PM debrief where the committee argued for 18 minutes and rejected a candidate who couldn't clearly explain how they handled cross-functional resistance. Wraps up with a seven-day weekly review and next week's prep direction.

Deep Dives

Behavioral & Ethics Interview Guide: AI Ethics, Teamwork, and Impact Narratives

Behavioral interviews aren't about improvisation — they're about a pre-prepared story library. AI Engineer behavioral interviews have unique focus areas: AI ethics (bias, fairness, privacy), technical decision impact narratives (why you chose this model/architecture), and experience driving ML projects across teams. Strategy: build 8-10 STAR stories, practice each until you can deliver it in under 2 minutes.

Coding Interview Guide: Strategies for ML-Flavored Programming Problems

AI Engineer coding interviews aren't identical to SWE — beyond LeetCode medium, you'll face ML-flavored problems (implementing a tokenizer, writing a batch inference pipeline, handling sparse matrices). Strategy: practice LeetCode medium to 70% pass rate, then spend remaining time on numpy/pandas operations, data processing pipelines, and ML-related programming problems.

Deep Learning Interview Guide: Core Intuitions from CNN to Transformer

Deep learning interviews don't ask you to derive backpropagation — they test whether you can explain the design intuition behind architectures. High-frequency topics: CNN's locality and translation invariance, why the evolution from RNN to Transformer was necessary, self-attention computation and complexity, BatchNorm vs LayerNorm use cases, and common training tricks (learning rate scheduling, gradient clipping, mixed precision).

LLM Application Design Interview Guide: From RAG to Agent Architecture

LLM Application Design is the hottest new interview topic in 2025-2026. Key focus areas: RAG pipeline chunking/retrieval/reranking design, agent tool-use and planning loops, context window management strategies, guardrails and safety design, and LLM application evaluation methods. Interviewers especially value whether you've hit real-world pitfalls.

ML Fundamentals Interview Guide: From Bias-Variance to Evaluation Metrics

ML fundamentals interviews don't test formula memorization — they test whether you can explain concepts intuitively and hold up under follow-up questions. High-frequency topics: the practical meaning of bias-variance tradeoff, the selection logic for L1/L2 regularization, why cross-entropy beats MSE for classification, SGD vs. Adam tradeoffs, and how precision/recall priorities differ by scenario.

ML System Design Interview Guide: From Requirements to Production Architecture

The core of ML System Design interviews isn't choosing the model — it's how to turn a business objective into a system that's deployable, monitorable, and iterable. Interviewers want to see if you can: translate business goals into ML objectives, design data pipelines and feature stores, choose reasonable serving strategies, and plan monitoring and A/B testing.

MLOps & Deployment Interview Guide: From CI/CD to Model Monitoring

MLOps interviews test whether you have experience pushing models to production. Key topics: ML pipeline CI/CD (how it differs from software CI/CD), model registry and version management, A/B testing design and pitfalls, inference scaling strategies (horizontal scaling, model compression, caching), and production monitoring and alerting design.

NLP & LLM Interview Guide: From Tokenization to RLHF

The dividing line in LLM interviews is whether you've actually used these things. High-frequency topics: BPE tokenization logic and multilingual challenges, pretraining objectives (CLM vs MLM), three levels of fine-tuning (full/LoRA/prompt tuning), RLHF workflow and failure modes, prompting as engineering practice, and the difficulty of LLM evaluation with current methods.

AI Engineer Interview Overview: From Company Types to Preparation Strategy

AI Engineer interviews go beyond ML — big tech emphasizes system design and coding, startups look for end-to-end delivery, and AI-native companies test LLM engineering depth. Strategy: identify your target company types first, then allocate prep time across six dimensions (ML fundamentals, system design, LLM applications, coding, paper reading, and behavioral).

Paper Reading Interview Guide: How to Read, Discuss, and a Must-Read List

Paper reading interviews don't test whether you've read that specific paper — they test whether you can quickly understand a new method and identify its limitations. AI-native companies (Anthropic, OpenAI) particularly favor this format. Strategy: practice reading a paper in 30 minutes and verbally stating contribution + limitation, build your own must-read list, and practice summarizing each paper in three sentences.

AI Product Design Interview Guide: From Human-in-the-Loop to Trust Building

AI Product Design is the hottest new interview topic in 2025-2026. Core areas: when to use AI (not every problem needs it), human-in-the-loop design patterns (when to let humans intervene), trust building (how to make users believe AI output), AI product challenges (hallucination, latency, cost), and AI product evaluation metrics.

Behavioral & Leadership Interview Guide: Influence, Conflict Resolution, and Vision

Product Builder behavioral interviews differ from SWE — they don't just test teamwork, they specifically test how you drive things without formal authority. Core skills: influence narratives (how to convince engineers to build your feature), conflict resolution (disagreements with designers/engineers/stakeholders), vision expression (how to make someone understand your product direction in 30 seconds), and failure stories (learning from failure without deflecting blame).

Execution Interview Guide: From Roadmap to Cross-Team Collaboration

Execution interviews test whether you can turn ideas into deliverables. Core skills: roadmap planning (how to prioritize with limited resources), priority defense (why A before B), cross-team collaboration (how to drive engineering and design), stakeholder management (how to handle conflicts), and the ability to track progress with data.

Growth & Experimentation Interview Guide: From Growth Loops to Experiment Design

Growth interviews don't test whether you can growth hack — they test whether you have systematic growth thinking. Core skills: growth loop design (the acquisition → activation → retention → referral flywheel), experiment design (the full hypothesis → metric → experiment → analysis process), retention strategy (finding the aha moment, designing habit loops), and using data to decide what's worth continued investment.

Metrics & Analytics Interview Guide: From North Star to Experiment Design

Metrics interviews test whether you can make decisions with numbers, not how much statistics you know. Core skills: north star metric selection logic (why this one and not that one), metric tree decomposition (finding actionable levers), funnel analysis (which step's drop-off is most worth fixing), A/B testing design and pitfalls, and judgment when facing counterintuitive data.

Product Builder Interview Overview: From PM to Builder Mindset

A Product Builder isn't a traditional PM — you need to build from 0 to 1, not just write PRDs. Interviews test the intersection of product intuition, metrics thinking, technical understanding, and execution ability. Prep strategy: first figure out whether your target company wants a PM or a Builder, then allocate time across nine dimensions.

Product Sense Interview Guide: From User Insight to Feature Prioritization

Product Sense interviews don't test how many features you can think of — they test whether you can find the problem truly worth solving within a vague requirement. Core skills: user segmentation thinking, problem reframing (turning 'add a feature' into 'what problem are we solving'), structured reasoning for feature prioritization, and the ability to hold or revise your judgment under follow-up questions.

Strategy Interview Guide: From Market Positioning to Competitive Moats

Strategy interviews don't test whether you can recite frameworks — they test whether you can make judgments with incomplete information. Core skills: market sizing (the practical use of TAM/SAM/SOM, not rote numbers), competitive moat analysis (network effects, switching costs, brand), go/no-go decisions for new markets, and using elimination rather than addition for strategic trade-offs.

Technical PM Interview Guide: From API Design to Architecture Understanding

Technical PM interviews don't require you to write production code, but you need to be able to read trade-offs. Core skills: API design fundamentals (RESTful, versioning, error handling), high-level system architecture understanding (microservices, database selection, caching), collaboration patterns with engineers (RFC process, technical spec review), and making product decisions under technical constraints.