Circle interview questions

Showing 1–10 of 10 results

• Describe pair-programming challenge under time pressureMedium

  Describe pair-programming challenge under time pressure evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  CircleSoftware EngineerBehavioral & LeadershipOnline Assessment
• Design banking payment scheduling systemHard

  This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Design banking payment scheduling system states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  CircleSoftware EngineerSystem DesignOnline Assessment
• Design flight-price search serviceHard

  Design flight-price search service evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  CircleSoftware EngineerSystem DesignOnline Assessment
• Design in-memory DB with TTL and backupHard

  A Circle software-engineer take-home: design a versioned in-memory key→(field→value) database with per-field TTL, append-only history and delete tombstones, lexicographically ordered scan and scanPrefix (correct even with special characters), and snapshot backup/restore counters. It exercises data modeling, time-travel visibility semantics, ordered indexing, garbage collection, and per-operation complexity trade-offs.

  CircleSoftware EngineerSystem DesignOnline Assessment
• Implement Recipe Storage CRUDHard

  This question evaluates the ability to design and implement in-memory data structures and APIs for CRUD operations, covering skills such as ID generation and parsing, string handling for case-insensitive uniqueness constraints, data modeling, and preserving original value casing.

  CircleSoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement a simplified multi-level banking systemMedium

  Implement a simplified multi-level banking system evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  CircleSoftware EngineerCoding & AlgorithmsOnline Assessment
• Implement cheapest itinerary with date filtersMedium

  This question evaluates proficiency in graph algorithms and constrained pathfinding, including handling date filters for initial departures, time-ordered connections, cycle avoidance, and quantitative complexity analysis.

  CircleSoftware EngineerCoding & AlgorithmsOnline Assessment
• In-Memory Bank System With Top-N Activity Ranking and Expiring Pending TransfersMedium

  Implement an in-memory banking class in stages: create accounts, deposit and pay, rank the top n accounts by transaction activity, and support transfers that hold funds until the recipient accepts within a time window or they are refunded. Tests state modeling, validation, and timestamp-driven expiry.

  CircleSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Trace and reduce redundant curl requestsMedium

  A practical curl interview question on tracing and reducing redundant HTTP requests: instrumenting a curl-based client, finding duplicate calls, and cutting request volume. Includes a full worked solution.

  CircleSoftware EngineerSystem DesignOnline Assessment
• Write PostgreSQL updates with date filtersMedium

  This question evaluates competency in PostgreSQL data manipulation, covering updates with correct timestamp handling, upserts with conflict resolution, date-range selection using timestamptz, and index design plus performance analysis with EXPLAIN ANALYZE.

  CircleSoftware EngineerData Manipulation (SQL/Python)Online Assessment