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

IntermediatePending

Apr 2026

Summary

Took the Anthropic OA for a software engineer role. It was a banking system problem, pretty close to something I'd seen before but with a couple of differences that ended up mattering more than I expected.

Questions Asked (1)

Implement a banking system with account management features, including scheduled payments and a getBalance() method that handles account merging and recreation correctly.

Algorithms & Data StructuresSystem DesignAPI & Integrations

Author's notes

The scheduled payment part was actually easier than a similar version I'd practiced before, so that was fine.

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AI HintsAI Generated

Suggested Approach

Start by clarifying requirements and edge cases, especially around account merging and recreation. Then design a data model that handles balances, scheduled payments, and account lifecycle events, and implement getBalance() to correctly compute balances after merges or recreations. Discuss trade-offs and test with scenarios like merging accounts with pending payments.

Pro tip: Demonstrate foresight by discussing idempotency and consistency in scheduled payments, and how to handle race conditions in concurrent account operations. This shows you think about real-world banking constraints.

1. Clarify Requirements and Edge Cases

Ask questions to understand account merging rules, recreation semantics, and scheduled payment behavior. Identify edge cases like merging accounts with pending payments or recreating a closed account.

2. Design Data Model and API

Define classes for Account, ScheduledPayment, and a BankingSystem. Decide how to represent account state, balances, and relationships to handle merges and recreations.

3. Implement Core Operations

Implement account creation, merging, recreation, and scheduling payments. Ensure getBalance() correctly aggregates balances from merged accounts and handles recreated accounts.

4. Handle Concurrency and Consistency

Discuss locking or transactional mechanisms to ensure scheduled payments and balance queries are consistent, especially during merges.

5. Test and Validate

Walk through test scenarios: merging accounts, recreating accounts, and executing scheduled payments. Verify getBalance() returns correct values in each case.

Key Points to Mention

Account merging: how to combine balances and pending payments, and update references.
Account recreation: whether to reuse IDs, reset balances, or preserve history.
Scheduled payments: how to store, execute, and handle failures or cancellations.
getBalance() semantics: should it include pending payments? How to compute after merges?
Concurrency: using locks or transactions to prevent race conditions.
Idempotency: ensuring scheduled payments are not executed multiple times.

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