Interview Guides
Real questions, follow-ups, and rubrics from people who know the process from the inside. One deep guide per company.
OpenAI's 5-Part Coding Interview Question
A real OpenAI grid-simulation coding question with all five parts and full Java solutions, plus the scoring rubric.
Anthropic's Image Processor Coding Question
Design an image processor, single-threaded then a concurrent worker pool. Full Java for both parts and the rubric.
Stripe's 3-Part Shipping Cost Coding Question
Build a shipping-cost calculator across three pricing models: flat, tiered, then fixed. Full Java for each part and the rubric.
Google's 3-Part Winning Tile Coding Question
Three parts: write the signature, implement the comparison, then absorb a spec change. Full Java per part and the rubric.
Airbnb's Terrain Water-Drop Coding Question
Render terrain, then simulate water settling into valleys. Full Java for both parts and the rubric.
Jane Street's 2-Part Tree Selection Question
A multiset selection over a tree, then a scored sliding window for the most valuable levels. Full Java for both parts and the rubric.
Meta's 3-Part AI-Assisted Coding Question
Meta's AI-assisted round: analyze the brute force, propose an optimization, then implement it. Full Java and the rubric.
The Intercom Interview: Minicom and Data Modeling
What to expect in Intercom's Minicom live-coding round and the data-modeling round, and how to prepare. The exact tasks are in the bank.
Atlassian's 3-Part Tennis Court Coding Question
Assign bookings to the fewest courts, then layer in two maintenance rules. Full Java for all three parts and the rubric.
Flexport's 3-Part Shipping Route Coding Question
Range updates on congestion, then range-min queries, then min and sum together. Full Java with a lazy segment tree and the rubric.
Palantir's Package Manager Concurrency Question
Turn a blocking package manager concurrent with futures, return on first success, and cache the right thing. Full Java per stage and the rubric.
Optiver's Reconciliation System Design Question
Reconcile two independent trade feeds, then evolve the design when the assumptions break. The staged design and the rubric.
Citadel's High-Performance Order Book Question
Build a price-time-priority order book with matching, then extend it to stop-loss, iceberg, and multi-exchange orders. Full Java and a detailed rubric.
HRT's Copy-on-Write String C++ Question
Implement a copy-on-write string in C++, from shared buffers and refcounts to copy-on-mutation and thread safety. Full C++ and a detailed rubric.
Glean's 2-Part Snack Bar Grid Question
Find a path through an office grid to a snack bar, then do it without the snack noise disturbing any boss. Full Java BFS and a detailed rubric.
Lyft's 3-Part Rating Service Question
Model rides and ratings, ingest the raw feed, and build APIs for the rating a user received and their average. Full Java and a detailed rubric.
Jump Trading's Card Set Detection Question
Detect the strongest of six ranked card sets from a hand, with exact tie-breaking. Full Java and a detailed rubric.
Millennium's Bid-Ask and Market-Making Question
Build a bid-ask spread class, then a market maker that quotes around a price, then make it skew with inventory. Full Java and a detailed rubric.
Tower Research's Streaming Failure Detector
Detect three failures within a time window over an infinite log stream, then bound memory and scale to many users. Full Java and a detailed rubric.
Point72's Streaming Median Question
Find the median of a data stream with two heaps, then approximate it under a memory limit, then merge sketches across machines. Full Java and a detailed rubric.