12 Palantir Technologies Software Engineer (New Grad) Interview Questions (2026)

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STAR. Palantir's core value is making sense of messy real-world data. Pick a project where data was missing, duplicated, or inconsistent. Walk through: how you assessed quality, what reconciliation logic you wrote, what assumptions you flagged to stakeholders. Be specific.

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Tie to specifics: the mission orientation (defense, healthcare, manufacturing), the Forward Deployed model, the ontology platform's approach to enterprise data. Avoid 'I want to work on hard problems' — too generic. If you have an opinion on Palantir's customer base (defense work included), have a coherent answer.

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STAR. Frame around tradeoffs. Show you understood the stakeholder's underlying need, not just the surface request. Palantir engineers work directly with customers — they need people who can disagree-and-commit, not pure order-takers.

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STAR. Palantir's Forward Deployed model means engineers learn customer domains (logistics, manufacturing, intelligence). Pick a project where you immersed in a new domain quickly, talked to domain experts, and shipped useful work. Show curiosity, not just technical chops.

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DFS with path accumulator. At each node, append to path; if leaf, push to results; recurse on children; backtrack. O(N) time, O(H·L) space where L is average path length. Edge cases: empty tree, single node, skewed tree.

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Doubly-linked list + hash map. Map key → node, node holds value. On get: move node to front. On put: insert at front, evict tail if over capacity. O(1) for both. Edge cases: capacity 0, update existing key. Show the wiring carefully — many candidates lose points on the doubly-linked list pointer manipulation.

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Sort by start. Iterate, merging into result if current.start <= last.end. O(N log N) time, O(N) space. Edge cases: empty input, single interval, all overlapping. Be ready for the follow-up: insert a new interval into a sorted non-overlapping list.

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Classic DP. dp[i][j] = LCS length of s1[:i] and s2[:j]. If chars match: dp[i][j] = dp[i-1][j-1] + 1. Else: max(dp[i-1][j], dp[i][j-1]). O(N·M) time and space. Reconstruct the actual sequence by walking back through the table.

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Entities: Shipment, Carrier, Transfer, Container. Relationships: Shipment has many Containers (split); Transfer links a Container from one Carrier to another. Discuss event-sourcing the lifecycle (each state change as an event) vs current-state snapshot. Palantir's bread and butter — they want to see you ask clarifying questions about the actual workflow before drawing boxes.

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Entities: User, Friendship. Friendship is symmetric — typically stored as a single edge (user_a_id, user_b_id) with canonical ordering (always a < b) to avoid duplication, OR two rows for fast lookup either direction. Discuss tradeoffs (storage vs query speed) and indexes. Palantir's ontology framing — model the real-world concept first, then the storage.

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Statistical baseline: rolling mean and std per host, flag values > k std deviations from mean. Threshold-based (simple but works). For seasonality: subtract a moving average that respects the period. Discuss false-positive rate and how a human-in-the-loop confirms anomalies — Palantir's operator-centric design.

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Pipeline: upload endpoint, async worker queue, validator, database writer. Discuss: partial-success semantics (per-row vs all-or-nothing), error reporting (return per-row results), large files (streaming parse not full-load). Palantir's product is full of CSV ingest — they will go deep.