Full Stack Developer
Practice Full Stack Developer questions on APIs, auth, Next.js rendering, databases, caching and deployment, from REST basics to system design.
- Questions
- 100
- Interview Qs
- 30
- Judged problems
- 135
- Skills
- 9
About the role
A Full Stack Developer builds a feature from the screen all the way to the database. On a normal day you might design an API endpoint, write the database query behind it, build the React page that calls it, and then deploy the change to production. You understand how the browser, the server, the database and the network fit together, so you can follow a bug from a button click to a slow SQL query.
The job needs breadth more than one narrow specialty. You should be comfortable with HTML, CSS and JavaScript or TypeScript, a frontend framework such as React or Next.js, a backend runtime such as Node.js, Python or Java, SQL databases, authentication, and basic cloud deployment. Just as important is good judgment: knowing where logic should live, how to keep secrets off the client, and how to ship small, safe changes.
As you grow, you own whole features or products, make architecture choices such as rendering strategy, caching and data modelling, review other people's code, and help the team keep the system secure, fast and easy to change.
Practise by level
Open the full question bank (100 questions) →Mock interview
Screening round
4 questions · 4 min each · pass 50%
mediumTechnical round
5 questions · 4 min each · pass 60%
hardFinal round
6 questions · 3 min each · pass 70%
Coding problems for full stack developers
- Alphanumeric Palindrome Checkeasy
- Balance Point of a Beameasy
- Balanced Bracket Stringeasy
- Banner From Letter Tileseasy
- Best K-Day Sales Windoweasy
- Best Single Trade Profiteasy
- Can One Person Attend Every Booking?easy
- Cancel Adjacent Twinseasy
- Collapse Repeated Readingseasy
- Compare Release Versionseasy
- Compress Character Runseasy
- Constant Diagonals Grideasy
SQL problems
All SQL problems →Skills in this track
Learning roadmap
- 1
Web fundamentals
Learn HTML, CSS and modern JavaScript well. Understand HTTP methods, status codes, headers, cookies and what the browser does when it loads a page.
- 2
Frontend framework
Learn React with TypeScript: components, state, effects and forms. Then learn Next.js App Router, Server Components and the difference between SSR, SSG and client rendering.
- 3
Backend and APIs
Build REST APIs with Node.js (Express, Fastify or Next.js Route Handlers) or another stack. Learn validation, error handling, pagination and how to structure a service.
- 4
Databases
Learn SQL with PostgreSQL: schema design, indexes, joins, transactions and migrations. Use an ORM such as Prisma or Drizzle, and know when to drop down to raw SQL.
- 5
Auth, security and deployment
Implement sessions or tokens, password hashing, CSRF and XSS protection. Deploy with Docker or a platform like Vercel, set up CI, environment variables and logging.
- 6
Portfolio projects
Build 2 to 3 complete apps with login, a database, file uploads and a real deployment. Be ready to explain every design choice and what you would change at larger scale.
Top Full Stack Developer interview questions
- What happens, step by step, when a user types your app URL into the browser and presses Enter?
- Design the REST API endpoints for a simple blog with posts and comments. What URLs, methods and status codes would you use?
- What is the difference between authentication and authorization? Give an example from a web app.
- You are starting a new e-commerce app. Would you choose a SQL or a NoSQL database, and why?
- Explain client-side rendering, server-side rendering and static site generation. When would you use each?
- In a web app with a React frontend and an API, where should input validation happen, and why?