Fullstack Engineer Technical Interview Questions
全栈工程师 · 技术面试（English interview practice）
Top Fullstack Engineer technical interview questions — architecture, system design, and hands-on problem solving. Practice explaining your approach out loud and get AI feedback on SpeakInterview.
- You need to design a multi-tenant SaaS application where tenants have varying data sizes and query patterns. How would you architect the database layer to ensure isolation, performance, and cost-efficiency? Discuss the trade-offs between shared schema, separate schema, and separate database per tenant.
- You need to design a system that allows users to upload large files (up to 2GB) and then process them asynchronously. How would you architect the frontend, backend, and database to handle this reliably? Discuss the trade-offs between synchronous vs asynchronous processing and how you would handle failures.
- Imagine you have a monolithic application that has grown complex, and you need to extract a new microservice for a specific domain (e.g., user authentication). What database strategy would you choose (e.g., shared database vs database-per-service) and how would you handle data consistency during the migration? Provide a concrete example from your experience.
- You need to improve the read performance of a REST API that returns aggregated data from multiple database tables. The current response time is 2 seconds, and you need to get it under 200ms. What approaches would you consider, and how would you choose between them?
- You are designing a multi-tenant SaaS application where each tenant has its own database schema for isolation, but you need to run cross-tenant analytics queries. How would you approach this from a database and system design perspective? Discuss the trade-offs between schema-per-tenant, shared schema with tenant ID, and a data warehouse for analytics. Provide a concrete example with numbers.