All 60 questions

  1. How would you design authenticated REST endpoints to create, retrieve, update, and delete library books?

    Asked in 2 of 377 interviews · last asked Jul 28 · Design · Mid-level

    Other ways it was asked
    • “How would you design REST API endpoints to create, retrieve, update, and delete books in a library management system, and how would you handle authentication?”
    • “How would you design REST API endpoints to create, retrieve, update, and delete books in a library management system, including pagination and response formats?”
    • “How would you design HTTP endpoints for a library application that supports adding and deleting books?”

  2. How does attribute routing work in ASP.NET Core Web API? Specifically, how do you map an action method to a particular URL and HTTP verb?

    Asked in 2 of 377 interviews · last asked Aug 15 · Tooling · Junior

    Other ways it was asked
    • “How does attribute routing work in an ASP.NET Core Web API, and how do you map an action to a specific URL and HTTP method?”

  3. Can you tell me the difference between a controller and a REST controller?

    Asked in 2 of 377 interviews · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What is the difference between a REST controller and a controller?”

  4. How can Apache Iceberg data be exposed through a REST API?

    Asked once · last asked Jun 9 · Design · Senior

  5. What design patterns would you use when building APIs with Node.js and Express?

    Asked once · last asked Jun 26 · Concept · Mid-level

    Other ways it was asked
    • “What design patterns have you used when building APIs with Node.js and Express?”
    • “Beyond using a consistent format for API responses and errors, what design patterns have you used with Node.js and Express? Can you give an example?”

  6. Besides authorization, roles, and permissions, what other use cases are appropriate for middleware?

    Asked once · last asked Feb 10 · Concept · Mid-level

  7. How would you expose a GET endpoint for an internal client to retrieve transactions using an account ID, and what technology or libraries would you use?

    Asked once · last asked Mar 5 · Design · Mid-level

  8. How would you design the backend architecture for mobile applications?

    Asked once · last asked Mar 6 · Design · Senior

  9. What would you normally include in health checks or health-check endpoints?

    Asked once · last asked Mar 9 · Concept · Mid-level

  10. In Spring Boot, how would you design a GET endpoint that accepts a user's ID and returns their information, including retrieving the data from the database?

    Asked once · last asked Mar 18 · Tooling · Mid-level

  11. When an API request creates or updates data, how does the application persist that data in the database?

    Asked once · last asked Mar 27 · Concept · Mid-level

  12. How would you structure and implement a simple user API that creates and retrieves a user—holding the user temporarily in memory or, alternatively, saving and retrieving it from a database—and returns appropriate HTTP status codes?

    Asked once · last asked Apr 9 · Write code · Mid-level

  13. How would you create an application and API using Node.js's built-in HTTP module without Express?

    Asked once · last asked Apr 16 · Tooling · Mid-level

  14. After receiving an HTTP PUT request with an object payload, how would an object storage service process and persist it?

    Asked once · last asked Apr 22 · Design · Senior

  15. What steps would you follow to add a new API to an existing back-end codebase?

    Asked once · last asked May 5 · Scenario · Mid-level

  16. How would you structure the backend of an API that performs tax calculations?

    Asked once · last asked May 7 · Design · Mid-level

  17. What are DTOs in NestJS?

    Asked once · last asked May 22 · Concept · Mid-level

  18. How does the WordPress REST API work?

    Asked once · last asked Jun 4 · Concept · Mid-level

  19. How do you add an endpoint in WordPress?

    Asked once · last asked Jun 4 · Tooling · Mid-level

  20. How do you create a REST API in Spring Boot?

    Asked once · last asked Jun 20 · Tooling · Junior

  21. How would you design a full-stack hotel reservation application for a packaging company, including its database, back end, and front end?

    Asked once · last asked Jun 24 · Design · Mid-level

    Other ways it was asked
    • “How would you design a full-stack hotel reservation application, including its database, back end, and front end?”

  22. How can microservices built with .NET Core expose functionality through REST APIs?

    Asked once · last asked Jun 25 · Concept · Mid-level

  23. How would you build an API endpoint that returns the current user's connections, like a friend list, from scratch?

    Asked once · last asked Jul 16 · Design · Mid-level

  24. For protected file downloads in WordPress, would you use a custom rewrite endpoint, a REST API route, or admin-ajax.php, and why?

    Asked once · last asked Jul 16 · Concept · Senior

  25. If asked to implement CRUD operations for a products table and report the best-selling products this month, how would you approach it?

    Asked once · last asked Jul 17 · Scenario · Mid-level

  26. How would you implement the backend logic for extending a user's subscription after they renew?

    Asked once · last asked Jul 22 · Scenario · Mid-level

  27. Can you walk through how an HTTP POST request is processed from the endpoint to the final response?

    Asked once · last asked Jul 26 · Scenario · Mid-level

  28. How would you configure networking so requests from an API gateway can reach a container?

    Asked once · last asked Jul 27 · Scenario · Senior

  29. In Node.js with Express, how do you structure a simple REST endpoint to create a resource, including request validation, error handling, and returning the correct HTTP status codes?

    Asked once · last asked Jul 27 · Tooling · Mid-level

  30. How does the order in which you register middleware components affect how requests are handled? Can you give an example of why order matters?

    Asked once · last asked Aug 5 · Scenario · Mid-level

  31. In Node.js/Express, how would you structure a REST API project’s folders or modules to keep routes, controllers, services, and data access cleanly separated?

    Asked once · last asked Aug 15 · Design · Mid-level

  32. How does ASP.NET Core Web API differ from ASP.NET Core MVC? What capabilities does Web API provide that MVC doesn't, and are there things MVC can do that Web API typically doesn't handle?

    Asked once · last asked Aug 15 · Concept · Mid-level

  33. Suppose you have a controller with a route template and an action that handles updating a user by ID. What would the attributes and route look like for that scenario?

    Asked once · last asked Aug 15 · Write code · Junior

  34. How would you implement a .NET endpoint for creating a new order?

    Asked once · last asked Aug 31 · Write code · Mid-level

  35. How do you implement CRUD operations in OData?

    Asked once · last asked Sep 2 · Tooling · Mid-level

  36. How should you define controllers and routes in TypeScript to handle requests and responses?

    Asked once · last asked Sep 13 · Concept · Mid-level

  37. Walk me through the process you follow to create a user creation API.

    Asked once · last asked Sep 15 · Tooling · Mid-level

  38. If you were reviewing a PR that introduces a new .NET microservice endpoint, what are the top five correctness and maintainability checks you'd perform before approving it?

    Asked once · last asked Sep 16 · Scenario · Senior

  39. What happens to a request after its initial validation in a REST API?

    Asked once · last asked Sep 18 · Concept · Mid-level

  40. How does an API controller handle an incoming request and return a response?

    Asked once · last asked Sep 18 · Concept · Junior

  41. Can you explain the difference between the MVC controller and the API controller?

    Asked once · last asked Sep 19 · Concept · Mid-level

  42. Would you use DTOs or entities to receive data from Angular, and why?

    Asked once · last asked Sep 29 · Concept · Mid-level

  43. How would you organize a Flask API?

    Asked once · last asked Oct 7 · Design · Mid-level

  44. Which Python technology or library would you choose first to build an internal API that integrates existing systems and supports bidirectional communication?

    Asked once · last asked Oct 13 · Scenario · Mid-level

  45. What responsibilities can a middleware layer serve between mobile apps and core services, and why might a team build one?

    Asked once · last asked Oct 23 · Design · Senior

  46. How do you create and manage REST APIs in Node.js?

    Asked once · last asked Sep 18 · Tooling · Mid-level

    Other ways it was asked
    • “How would you create and secure REST APIs in Node.js?”
    • “How would you create a basic REST API in Node.js?”

  47. In Spring Boot, which annotation would you use to define a REST controller, and what other annotations or components might it need?

    Asked once · last asked Mar 18 · Concept · Junior

  48. How would you structure an API using Django?

    Asked once · last asked Mar 19 · Design · Senior

  49. How do you define routes in a Node.js application?

    Asked once · last asked Apr 3 · Tooling · Junior

  50. Can you give me an example of a REST API that creates a user or retrieves one from a database?

    Asked once · last asked Apr 9 · Write code · Junior

  51. What is an API route in Next.js?

    Asked once · last asked Jun 1 · Concept · Junior

  52. What is the most widely used library for building APIs in Python? How do you make API calls, which HTTP methods do you know, and what do you pay attention to?

    Asked once · last asked Jun 18 · Concept · Mid-level

  53. What are interceptors, and what do they intercept?

    Asked once · last asked Jul 31 · Concept · Mid-level

  54. What are CRUD operations?

    Asked once · last asked Sep 6 · Concept · Junior

  55. If you had to write an API, what would you do?

    Asked once · last asked Sep 15 · Scenario · Mid-level

  56. How would you generate multiple APIs and iterate over them?

    Asked once · last asked Sep 18 · Scenario · Mid-level

  57. Can you create a basic REST API in Node.js and show its output using console.log?

    Asked once · last asked Sep 18 · Write code · Junior

  58. How would you debug and fix an API issue in an existing code change?

    Asked once · last asked Sep 22 · Scenario · Mid-level

  59. How do the client, back-end API, and database interact on a typical create-item request?

    Asked once · last asked Oct 14 · Scenario · Junior

  60. How would you design and implement a REST API for managing employees?

    Asked once · last asked Oct 19 · Write code · Mid-level

More REST API interview questions

How this list is made

Every question here was asked by a real interviewer in a real job interview that a candidate ran MeetAssist in. After the call, the interviewer's questions are pulled from the transcript. Practice sessions, tests, exams and anything that was not a job interview are dropped.

Questions are rewritten so they make sense on their own: names of people, employers and clients are removed, and speech-to-text mistakes are fixed. Small talk, logistics and questions about one candidate's own résumé are left out. Rephrasings of the same question are merged, and the count is the number of different interviews it came up in.

The interviews come from candidates who use MeetAssist, so they lean towards software, data and AI roles: the shares describe these interviews, not every REST API interview. Answers to the most asked questions are written and checked by an editor; a "common mistake" is shown only when reviews of real answers in these interviews show it, with the count.

377 interviews, 243 candidates, Jan 2026 to Oct 2026. Updated every month with new interviews.