Interview questions

Build API integration to categorize job types using Scale AI

Create a feature that calls Scale AI's internal API to categorize different types of jobs using their LLM services. Implement proper API integration with appropriate…

Companies: Scale AI

Last reported Oct 2025

Refactor a Tennis Score Program

Review and refactor three separate tennis score tracking programs that contain intentionally poor code. Identify the issues and improve the code quality, structure, and…

Companies: Fountain

Last reported May 2025

Analyze TypeScript dependencies with limited model disclosure

Parse imports and cycles, then obtain structured model feedback without sending complete source files.

Companies: QuickBase

Build a concurrent database buffer pool

Manage page pinning, dirty writes, asynchronous disk I/O, and adaptive replacement with resident and ghost histories.

General practice

Build a constrained multiple-choice field editor

Validate the label and unique choices, enforce a 50-choice limit, and insert an absent default choice when saving.

Companies: QuickBase

Build a healthcare-rate table and visualization

Fetch rate records, display useful provider and payer fields, and visualize a meaningful pattern. Practice requires fixtures or permitted API access.

Companies: Serif Health

Build a pipeline metadata editor

Load channels, maintain at most five distinct tags, validate the label, and report submission success.

Companies: QuickBase

Build a streaming JSON primality service

Serve ordered TCP requests, distinguish noninteger numbers, validate message shapes, and close malformed sessions.

General practice

Build a tariff-aware EV charging interface

Implement time-dependent prices, choose a cheapest continuous charging window, and update charger state through GraphQL subscriptions.

Companies: DejaBlue

Build an approval-gated ticket agent

Stream tool traces, isolate ticket access by tenant, and enforce user approval for changes despite malicious ticket content.

Companies: QuickBase

Build an ordered checkout-rule composer

Calculate server receipts with integer cents, ordered discounts, half-up rounding, and server-only tax; persist rules rather than totals.

Companies: QuickBase

Build insurer-rate ingestion and billing-code search

Resolve rate files, normalize nested records, and expose billing-code search with optional provider identifiers.

Companies: Serif Health

Build interactive beginner coding lessons

Create a lesson API and UI that loads lessons individually, guides a beginner through a button exercise, and records completion.

Companies: Mimo

Build partition-tolerant gossip broadcast

Replicate accepted values across nodes after partitions heal; treat message efficiency as an extension of the same exercise.

General practice

Implement a concurrent B+ tree with deferred deletion

Preserve buffered tombstones through splits and merges, and support concurrent lookup, mutation, and ordered iteration.

General practice

Implement a datagram key-value protocol

Separate UDP inserts from lookups using the first equals sign; preserve empty values and the immutable version key.

General practice

Implement a negotiated byte-cipher service

Parse reversible transformations, reject identity ciphers, and apply the correct stream positions during decoding and encoding.

General practice

Implement course progress and achievement tracking

Model ordered lessons, repeated attempts and timestamps, then calculate progress toward lesson, chapter, and course achievements.

Companies: Mimo

Implement snapshot reads using MVCC undo chains

Reconstruct visible tuples, detect write conflicts, and retain versions required by active readers.

General practice

Parallelize blocking API requests while preserving order

Implement concurrent execution for a list of blocking API requests. Limit the number of workers. Return each result in the position of its input, even…

Companies: Baseten

API Design · Concurrency · Thread Pools

Preserve read-committed transactions during partitions

Reconcile replicated reads and writes while preventing aborted and intermediate reads. This does not promise serializable isolation.

General practice

Provide reliable line reversal over UDP

Implement sessions, ordered byte positions, acknowledgements, and retransmission before reversing complete application lines.

General practice