Palantir interview, and the decomposition round.

Most engineering candidates finish in three to four weeks. Deployment strategists tend to be quicker at two to three, and product designers slower at four to eight because the design challenge runs asynchronously. Palantir does not publish who makes the final call, so accounts describing a hiring-manager-led decision are community-reported rather than official. Recruiter screen: Motivation specific to Palantir's products, willingness to travel, and eligibility for security clearance. The mission question is asked early and asked again later, and a general interest in data infrastructure does not survive the second time. Technical screen: The online version has three parts: a coding problem framed as a small project, a SQL task joining and aggregating across tables to answer a business question, and a REST API task such as fetching paginated data and filtering it by date. The live version tests the same ground with communication weighted as heavily as correctness. Decomposition: A deliberately huge and underspecified problem, worked in two phases. First you break it down and agree an approach with the interviewer, then you sketch a high-level design, a data model and the APIs, with minimal or no code. Graders look for structured handling of ambiguity, a clear view of who the end user is and what decision changes for them, honest reasoning about data sources and freshness, and a scoped first version with success metrics. Working in silence is the reported way to fail it. Learning and re-engineering: Learning gives you unfamiliar code in Python, Java, C++ or TypeScript and asks you to understand it out loud. Re-engineering gives you 80 to 250 lines with logic bugs in them and asks you to find and fix them. Both are comprehension tests rather than writing tests. Coding and system design: Conventional algorithm work and platform design, with behavioural content of 15 to 20 minutes embedded in the rounds rather than separated out. Hiring manager interview: Revisits whichever onsite round went worst, then goes at ownership, reflection on failure, and mission alignment. The why-Palantir question is pushed two or three layers deep here, and surface-level answers are named by the company as a top reason strong candidates are turned down.

Palantir screens for a specific temperament more openly than most companies do, and it says plainly that technical strength alone does not carry a candidate through. Conviction about the mission, tied to a product. An answer that names Gotham, Foundry or AIP and what it does survives the follow-up. One about interesting data problems does not A considered position on government and defence work. The loop asks, and an honest answer is acceptable where an unconsidered one is not Structure under ambiguity. The whole decomposition round exists to see whether you can impose order on an open problem without a template Ownership with numbers, and reflection on failure. Achievements are probed for what you personally decided and what you would do differently Low ego. Interviewers push back during the rounds, and how you take the pushback is part of what is being observed

Behavioural content is embedded inside the technical rounds rather than given its own stage, so these questions arrive with a problem still on the screen. The decomposition prompts below are the ones candidates report by name. Why Palantir, and which product? Tell me about something ambiguous you owned end to end. How do you feel about working on government and defence problems? Tell me about a project that failed and what you concluded from it. Walk me through a decision where you had to pick a first version and cut the rest. Design a system that keeps two employee record systems in sync. How would you improve traffic in New York City? Decomposition SQL and data reasoning Reading and repairing code REST APIs and pagination

Rehearse decomposition out loud, because silence is the reported way to fail it. Take a large problem, set a timer for an hour, and narrate: who uses this, what decision changes for them, what data you would need, what you would ship first, and how you would know it worked. Do not open with a framework. Interviewers report rejecting candidates who start with a consulting structure, and the round is testing whether you can build a structure for this problem rather than fit it to one you already had. Have a real answer to why Palantir that names a product. The question is pushed two or three layers deep by the hiring manager, and Palantir says shallow motivation is a top reason it turns down strong engineers. Decide what you think about defence work before you are asked. A considered position is acceptable either way, and an unprepared one is the answer that costs the offer. Practise reading rather than writing. Open unfamiliar code, explain what it does out loud, then plant a logic bug in a file and find it cold. Those are two of the rounds. Get SQL joins and aggregation fluent. They appear in the 90-minute screen and again whenever a design answer has to say where the numbers come from.