Anthropic·Software Engineer·Online Assessment (OA)·Intermediate

Intermediate

Jun 2026Remote

Summary

Anthropic's CodeSignal OA for a software engineer role is a multi-level banking system problem where each level stacks new requirements on top of the last. It's the kind of thing that feels manageable until you're three levels deep juggling scheduled payments and partial transfers simultaneously.

Questions Asked (1)

Design and implement a banking system that supports account creation, deposits, withdrawals, and transfers, then extend it across multiple levels to add scheduled payments, cashback logic, and partial transfer completion when funds are insufficient.

System DesignAlgorithms & Data StructuresTechnical Trade-offs

Author's notes

The base level feels like a warmup but don't let that fool you.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying requirements and defining core data models and operations for a single-account banking system, then iteratively extend the design to handle multi-account transfers, scheduled payments, cashback, and partial transfers. Emphasize modularity, transactional consistency, and error handling, and discuss trade-offs between simplicity and scalability.

Pro tip: Demonstrate foresight by discussing how you would test edge cases like concurrent transfers and insufficient funds, and how you'd evolve the design for real-world constraints like idempotency and audit logging.

1. Clarify Requirements and Scope

Ask clarifying questions about expected scale, consistency needs, and specific behaviors (e.g., overdraft policies, cashback rules). Define the core entities: Account, Transaction, and their relationships.

2. Design Core Banking Operations

Outline data structures and algorithms for account creation, deposit, withdrawal, and transfer. Ensure atomicity and discuss locking or optimistic concurrency for transfers.

3. Extend with Scheduled Payments and Cashback

Introduce a scheduler for future-dated payments and a cashback engine that credits accounts based on transaction rules. Discuss how to handle failures and retries.

4. Implement Partial Transfer Completion

Design logic to transfer as much as possible when funds are insufficient, updating both accounts and recording the partial amount. Consider how to notify users and handle subsequent top-ups.

5. Address Trade-offs and Scalability

Discuss trade-offs between consistency and availability, and how the design scales with sharding or microservices. Mention monitoring, idempotency, and audit trails.

Key Points to Mention

Transactional integrity and ACID properties for transfers
Concurrency control (e.g., locks, optimistic concurrency) to prevent race conditions
Idempotency for scheduled payments and retries
Data model design for accounts, transactions, and scheduled jobs
Error handling and user notification for partial transfers
Scalability considerations: partitioning, event sourcing, or CQRS

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.