Design a high-throughput Load Balancing System

Last updated: September 26, 2025

Quick Overview

Design a high-throughput load balancing system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

TikTok
Software Engineering Fundamentals
Software Engineer
TikTok
September 26, 2025
Software Engineer
Technical Screen
Software Engineering Fundamentals
Easy

133

6

4,791 solved


Design a high-throughput load balancing system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

TikTok asks this during the Technical Screen to assess your depth in software engineering. They want to see understanding of design patterns, system architecture, and the trade-offs involved in different technical approaches.

What the Interviewer Expects
  • Explain the concept clearly with a practical example
  • Discuss when and why to apply this principle
  • Identify common mistakes and anti-patterns
  • Compare with alternative approaches
Key Topics to Cover
Design patterns (Factory, Observer, Strategy, etc.)
Version control and branching strategies
SOLID principles
API design and RESTful conventions
Concurrency and thread safety
Testing strategies (unit, integration, e2e)
How to Approach This
  1. Apply SOLID principles. Single Responsibility makes code testable, Open/Closed makes it extensible.
  2. Choose data structures based on access patterns, not familiarity.
  3. Prefer immutable data and message passing over shared mutable state for concurrency.
  4. Design APIs with RESTful conventions, versioning, meaningful errors, and pagination from day one.
Possible Follow-up Questions
  • What testing strategy would you use for this component?
  • How would this design change if the team size doubled?
  • How would you document this for other engineers?
  • How would you measure the performance of this component in production?
Practice a Similar Problem on Codemia

Solve a related problem with our interactive workspace, get AI feedback, and view detailed solutions.

Solve on Codemia
Sample Answer
Core Principles

Start by identifying which engineering principles are most relevant: **SOLID Principles**: Single Responsibility (one reason to change), Open/Closed ...

Design Approach

**API Design**: Define clear interfaces before implementation. Use RESTful conventions for HTTP APIs. Version your APIs from the start. Return meaning...


Submit Your Answer
Markdown supported

Related Questions