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Goldman Sachs·Software Engineer·Online Assessment (OA)·Junior

JuniorPending
Jul 2026

Summary

Took the Goldman Sachs OA and honestly wasn't sure what to expect, but it ended up being the easiest online assessment I've ever sat through. FizzBuzz and a basic REST API. First time I've walked away from an OA feeling like I actually nailed everything.

Questions Asked (2)

Q1

Implement FizzBuzz.

Algorithms & Data Structures
Author's notes

I've done this so many times it's basically muscle memory at this point.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem requirements (e.g., range, output format) and then implement a clean, efficient solution using a loop with conditional checks. Discuss edge cases and potential optimizations, and be prepared to explain your code and test it with examples.

Pro tip: Even for simple problems, demonstrate professionalism by writing modular, testable code and discussing time/space complexity. Mention that FizzBuzz can be solved without the modulo operator using counters, showing deeper algorithmic thinking.

1. Clarify Requirements

Ask about the range (e.g., 1 to 100), output format (print or return list), and any constraints. Confirm whether to use standard FizzBuzz rules.

2. Plan the Solution

Outline a loop from 1 to n, checking divisibility by 3 and 5. Decide on order of conditions to avoid redundancy (e.g., check both first).

3. Implement the Code

Write clean code with meaningful variable names. Use modulo operator for simplicity, but be ready to discuss alternatives.

4. Test and Validate

Walk through a few iterations (e.g., 1, 3, 5, 15) to verify correctness. Mention edge cases like n=0 or negative numbers if applicable.

5. Analyze and Optimize

State time complexity O(n) and space O(1). Discuss potential optimizations or alternative approaches (e.g., string concatenation, counter method).

Key Points to Mention

  • Modulo operator for divisibility checks
  • Order of conditions (check both 3 and 5 first)
  • Time and space complexity analysis
  • Edge cases (e.g., n=0, negative numbers)
  • Alternative implementations (e.g., without modulo using counters)
  • Code readability and maintainability

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

Q2

Build a basic REST API.

API & IntegrationsSystem Design
Author's notes

Nothing tricky here.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the requirements and constraints of the API, such as the domain, expected load, and security needs. Then outline a high-level design covering endpoints, data models, and technology stack, and finally dive into implementation details for one or two key endpoints. Emphasize best practices like RESTful principles, error handling, and scalability.

Pro tip: Demonstrate awareness of financial industry constraints like data sensitivity, audit trails, and low-latency requirements, and mention how you would handle them in your design. This shows you understand the context beyond just coding.

1. Clarify Requirements

Ask questions to understand the API's purpose, expected traffic, data sensitivity, and integration points. This ensures your design meets the actual needs.

2. Design API Contract

Define resource endpoints, HTTP methods, status codes, and request/response formats. Use RESTful conventions and consider versioning.

3. Choose Technology Stack

Select appropriate frameworks, databases, and tools based on requirements, such as Node.js/Express for rapid development or Spring Boot for enterprise robustness.

4. Implement Core Endpoints

Write code for key endpoints, including routing, validation, business logic, and data persistence. Highlight error handling and input sanitization.

5. Address Non-Functional Aspects

Discuss security (authentication, authorization, encryption), scalability (caching, load balancing), and monitoring (logging, metrics).

Key Points to Mention

  • RESTful principles: statelessness, resource-based URLs, proper use of HTTP methods and status codes
  • Data validation and sanitization to prevent injection attacks and ensure data integrity
  • Authentication and authorization mechanisms like OAuth 2.0 or JWT, especially for financial data
  • Error handling with consistent error response formats and appropriate status codes
  • API versioning strategies to manage changes without breaking clients
  • Performance considerations: caching, pagination, rate limiting, and asynchronous processing

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