What should you focus on for a full stack interview?

Which topics stand out for this role?

Look beyond frontend and backend coding. System design and architecture appeared in 45% of these interviews, compared with 20% across all interviews. React, REST API design, JavaScript, performance work, and relational databases also appeared more often than average.

Mid-level questions made up the largest share, with junior and senior questions also included. Check your language basics, but also check whether you can explain architecture, scaling, and production troubleshooting.

  • Can you explain authentication and authorization for an API?
  • Can you explain what database indexes, transactions, and normalization do?
  • Can you explain how you would use profiling to investigate a performance problem?

Which common questions should you check first?

The most asked question was about daily use of AI tools, asked in 20 of 267 interviews. Dependency injection followed, in 14 of 267 interviews.

Other common questions give you specific points to check:

  • Can you explain how the JavaScript event loop works?
  • Can you say when you would choose PostgreSQL over MongoDB?
  • Can you compare server-side and client-side rendering in Next.js?
  • Can you explain useEffect and other React Hooks?
  • Can you explain what happens internally when you use await in C#?

What was missing from real answers?

For AI use, explain the task, not just the tool name. Some reviewed answers did not show how AI fitted into a real development task, from the initial input through implementation to a verified result. Can you describe what you gave the tool, how you used its output, and how you checked the result?

For dependency injection, some reviewed answers missed how it reduces coupling and makes dependencies easier to replace. Can you explain how it makes code less tightly linked, then connect easier replacement to testing and maintenance? A definition alone does not cover those points.

Which coding tasks can you work through?

Coding tasks appeared in 32 of 267 interviews. Use these tasks to check whether you can turn an approach into working code:

  • Find the length of the longest consecutive sequence in a list of integers.
  • Move the top card to another pile. Then move the remaining cards from the original pile, alternately placing them under and on top of the new pile until the original is empty.
  • Write a function that takes an array of numbers and returns only the even numbers.

What Full Stack Developer interviews cover

System design & architecture45% of interviews
Performance optimization & profiling31% of interviews
REST API design28% of interviews
Relational databases27% of interviews
React25% of interviews
JavaScript23% of interviews

The 20 most asked Full Stack Developer questions

Counted by interview, not by mention: a question asked twice in one conversation counts once.

  1. How do you use AI in your day-to-day software development, and which tools do you use?

    Asked in 20 of 267 interviews · last asked Oct 22 · Tooling

    Show answer

    I use GitHub Copilot for code suggestions and ChatGPT to explain errors, compare approaches, and suggest tests. For a bug, I share a small, sanitized example, review the suggested fix, adapt it to our code, and run tests to verify it. I follow company policy and never share secrets or restricted code.

    • Name tools you actually use and explain what each helps with.
    • Give one real task, from your input to implementation and verification.
    • Review generated code for correctness, security, and fit with the project.
    • Treat AI output as a suggestion, not proof that a solution works.

    What the interviewer checks: The interviewer is checking whether you use AI practically while taking responsibility for code quality and data safety.

    Common mistake (in 5 of 9 reviewed answers): Many answers forget that naming tools is not enough; explain what you gave the AI, what you changed, and how you verified the result.

    Other ways it was asked
    • “How do you use AI in your work?”
    • “How do you use AI tools in your software development workflow, and what tasks do they help with?”
    • “How do you use AI tools to write or develop software?”

  2. What is dependency injection?

    Asked in 14 of 267 interviews · last asked Oct 15 · Concept · Junior

    Show answer

    Dependency injection means giving a class the objects it needs instead of having it create them itself. These objects are usually passed through the constructor. This reduces coupling and makes them easier to replace for testing or maintenance. In .NET, the built-in DI container creates and supplies registered services.

    • Dependencies come from outside the class, usually through its constructor.
    • Using interfaces lets you replace implementations without changing the class that uses them.
    • Tests can supply fake dependencies instead of calling real databases or external APIs.
    • A DI container helps manage dependencies, but dependency injection also works without one.

    What the interviewer checks: The interviewer checks whether you understand how dependency injection reduces coupling and makes code easier to test and maintain.

    Common mistake (in 3 of 5 reviewed answers): Many answers forget that dependency injection reduces coupling, so explain how replacing dependencies helps testing and maintenance.

    Other ways it was asked
    • “What is dependency injection in .NET?”
    • “What is dependency injection, and when would you use it?”
    • “What is dependency injection in an API?”

  3. How does the JavaScript event loop work?

    Asked in 10 of 267 interviews · last asked Oct 7 · Concept · Mid-level

    Show answer

    The event loop coordinates when JavaScript runs queued callbacks. Synchronous code runs on the call stack, while the runtime handles timers and I/O. Once the stack is empty, microtasks, such as Promise callbacks, run before the next task, such as a timer callback.

    • Long synchronous work blocks other callbacks on the same thread.
    • Microtasks drain completely, including newly added microtasks, before the next task.
    • A timer delay sets a minimum wait, not an exact execution time.
    • Browsers and Node.js schedule work differently; Node.js uses phases and a separate process.nextTick queue.
    JavaScript
    setTimeout(() => console.log('timer'), 0);
Promise.resolve().then(() => console.log('promise'));
console.log('sync');
// Output: sync, promise, timer

    What the interviewer checks: The interviewer checks whether you can explain callback order and why asynchronous code does not prevent synchronous work from blocking.

    Other ways it was asked
    • “What is the event loop in JavaScript?”
    • “What does the event loop do in Node.js?”
    • “What is the JavaScript event loop?”

  4. How do SQL and NoSQL databases differ, and when would you choose PostgreSQL over MongoDB?

    Asked in 10 of 267 interviews · last asked Oct 21 · Concept · Mid-level

    Show answer

    SQL databases use relational tables; NoSQL databases use models such as documents, keys and values, or graphs. I would choose PostgreSQL for related data, joins, and strong database constraints. I would choose MongoDB when data fits flexible documents that are usually read or updated together.

    • PostgreSQL supports foreign keys and joins, which help manage relationships between tables.
    • MongoDB supports nested documents and optional schema validation; PostgreSQL also supports JSON data.
    • Both support transactions, so NoSQL does not mean no transactions.
    • Choose based on data structure, query patterns, and scaling needs, not just SQL versus NoSQL.

    What the interviewer checks: The interviewer checks whether you can match database features to application needs without relying on stereotypes.

    Other ways it was asked
    • “What is the difference between SQL and NoSQL databases?”
    • “How would you explain the difference between using MongoDB and PostgreSQL for a project, and when would you choose one over the other?”
    • “Why did you choose PostgreSQL over MongoDB?”

  5. What's the difference between server-side rendering and client-side rendering in Next.js?

    Asked in 8 of 267 interviews · last asked Oct 2 · Concept · Mid-level

    Show answer

    Server-side rendering (SSR) builds page HTML on the server for each request, while client-side rendering (CSR) builds content in the browser using JavaScript. SSR helps deliver visible content early and supports search indexing. CSR suits private dashboards where search indexing matters less, but users may wait for JavaScript and data before seeing content.

    • Next.js can mix server-rendered content with client-side interactivity.
    • Hydration adds browser interactivity to server-rendered HTML.
    • In Next.js, 'use client' does not mean client-only rendering; Client Components can also be pre-rendered.
    • SSR adds server work per request; CSR shifts rendering work to the browser.

    What the interviewer checks: The interviewer checks whether you understand where rendering happens and how it affects loading, search indexing, and interactivity.

    Other ways it was asked
    • “What is the difference between server-side rendering (SSR) and client-side rendering (CSR) in Next.js?”
    • “When would you use client-side rendering rather than server-side rendering in Next.js?”
    • “What is server-side rendering in Next.js?”

  6. What are the differences between var, let, and const in JavaScript and TypeScript?

    Asked in 7 of 267 interviews · last asked Oct 1 · Concept · Junior

    Show answer

    `var` is not block-scoped; `let` and `const` are. `let` allows reassignment, while `const` prevents reassignment but still allows changes inside objects and arrays. I use `const` by default, `let` when reassignment is needed, and avoid `var` in new code. TypeScript follows the same runtime rules and adds compile-time type checks.

    • `var` is function-scoped inside functions; top-level scope depends on whether the code is a script or module.
    • `var` declarations are hoisted and initialized to `undefined`; their assignments are not hoisted.
    • `let` and `const` are hoisted but cannot be accessed before initialization: this is the temporal dead zone.
    • `var` allows repeated declarations of the same variable; `let` and `const` forbid redeclaration in the same scope.

    What the interviewer checks: The interviewer is checking whether you understand scope, reassignment, initialization, and safe variable choices.

    Other ways it was asked
    • “What is the difference between var, let, and const in JavaScript?”
    • “What is the difference between var, let, and const?”
    • “Explain let, const, and var. What is the difference between these three?”

  7. What is React, and why is it used?

    Asked in 7 of 267 interviews · last asked Sep 13 · Concept · Junior

    Show answer

    React is a JavaScript library for building user interfaces. It lets me build reusable components and describe what the screen should show for the current data. React updates the UI when that data changes, which helps me manage interactive pages without manually changing the DOM.

    • Components split the UI into smaller, reusable parts.
    • Props pass data to components; state holds data that can change.
    • React focuses on the UI; routing and other app features often need additional tools.

    What the interviewer checks: The interviewer is checking whether you understand React’s purpose, component model, and main benefits.

    Other ways it was asked
    • “What is React?”
    • “What is React, and what is it used for?”
    • “What is React, and what advantages does it offer?”

  8. What is useEffect in React?

    Asked in 7 of 267 interviews · last asked Oct 2 · Concept · Junior

    Show answer

    useEffect is a React Hook that keeps a component in sync with external systems after React commits an update. I use it for subscriptions, timers, or fetching data. It can return a cleanup function to stop or undo that work. It was introduced in React 16.8.

    • Effects run on mount; dependencies control later runs. No dependency array means running after every commit.
    • An empty dependency array prevents reruns from changed props or state; development Strict Mode adds a setup-cleanup cycle.
    • Cleanup runs before the effect runs again with changed dependencies, and when the component unmounts.
    • Include every reactive value the effect reads in its dependencies. Calculate values during rendering when possible.

    What the interviewer checks: The interviewer checks whether you understand when effects run, how dependencies work, and why cleanup matters.

    Other ways it was asked
    • “What is the useEffect hook in React, and when would you use it?”
    • “What is React's useEffect hook used for?”
    • “Can you explain useEffect in React?”

  9. How do async and await work in C#, and what happens internally when you await?

    Asked in 6 of 267 interviews · last asked Sep 28 · Concept · Mid-level

    Show answer

    In C#, `async` lets a method use `await`, usually returning a `Task` or `Task<T>`. The compiler turns the method into a state machine. When an awaited operation is unfinished, the method saves its state and registers a continuation without blocking the thread. This improves scalability for I/O work without automatically creating a new thread.

    • If the awaited operation is already complete, execution continues immediately without pausing.
    • The continuation resumes the method from the await point when the operation completes.
    • Task awaits normally capture an available synchronization context; ConfigureAwait(false) avoids requiring that context when resuming.
    • Await returns the operation's result or throws its exception; async does not make CPU work faster.

    What the interviewer checks: The interviewer checks whether you understand suspension, continuations, and why asynchronous I/O avoids blocking threads.

    Other ways it was asked
    • “What are async and await in C#, and how do they support asynchronous programming?”
    • “What are async and await in C#, and why are they important?”
    • “What happens behind the scenes when you use async and await in C#—and why does it matter?”

  10. How do React Hooks work, and can you explain some commonly used hooks?

    Asked in 6 of 267 interviews · last asked Sep 3 · Concept · Junior

    Show answer

    React Hooks let function components use state and other React features without classes. React tracks hook calls by their order across renders. useState stores state, and its setter requests a render. useEffect synchronizes with external systems after a commit; useContext reads context, and useRef stores a value whose changes do not trigger renders.

    • Call these hooks at the top level of function components or custom hooks, not inside conditions or loops.
    • Effects need correct dependencies and cleanup for things like subscriptions and timers.
    • useMemo caches calculated values; useCallback caches functions. Both are performance tools, not requirements for correct code.
    • Custom hooks share reusable logic, but each call has its own state.

    What the interviewer checks: The interviewer checks whether you understand state, renders, effects, and the rules for using hooks safely.

    Other ways it was asked
    • “How do hooks work in React?”
    • “What are the hooks available in React?”
    • “How do state and Hooks work in React?”

  11. What’s the difference between authentication and authorization?

    Asked in 6 of 267 interviews · last asked Oct 7 · Concept · Junior

    Show answer

    Authentication checks who you are. Authorization checks what you are allowed to do. In an API, checking your login token is authentication; checking whether you can delete a record is authorization.

    • A valid login does not give access to every resource.
    • Authorization can depend on roles, permissions, or who owns a resource.
    • Enforce access rules on the server, not just in the user interface.

    What the interviewer checks: The interviewer is checking whether you separate identity checks from permission checks and enforce both correctly.

    Other ways it was asked
    • “What is the difference between authentication and authorization?”
    • “What is the difference between authentication and authorization in APIs?”
    • “How do authentication and authorization differ?”

  12. Can you explain closures in JavaScript?

    Asked in 5 of 267 interviews · last asked Oct 15 · Concept · Junior

    Show answer

    A closure lets a function keep access to variables from the scope where it was created, even after the outer function finishes. It keeps access to those variables, not frozen copies of their values. Closures are useful for private state, callbacks, and functions that remember values between calls.

    • Variable access depends on where the function is created, not where it is called.
    • Each call to an outer function can create separate state.
    • Closures can read and update variables in their outer scope.
    JavaScript
    function createCounter() {
  let count = 0;
  return function () {
    count += 1;
    return count;
  };
}
const next = createCounter();
console.log(next()); // 1
console.log(next()); // 2

    What the interviewer checks: The interviewer is checking whether you understand variable scope and how functions keep access to state.

    Other ways it was asked
    • “What is a closure in JavaScript?”
    • “Why are closures used in JavaScript?”
    • “What are closures in JavaScript?”

  13. In JavaScript, what is the difference between == and ===, and when would you choose one over the other?

    Asked in 5 of 267 interviews · last asked Aug 12 · Concept · Junior

    Show answer

    === compares values without converting types, while == may convert types before comparing. I use === by default to avoid unexpected matches. I use == only when I want its conversion rules, such as value == null to check for either null or undefined. Both operators compare two arrays by reference, not by their contents.

    • Different types always fail ===, but may match with ==.
    • Two separate arrays are not equal, even if their contents match.
    • NaN is not equal to itself with either operator.
    JavaScript
    0 == '0';           // true
0 === '0';          // false
undefined == null;  // true
undefined === null; // false
const a = [1];
const b = [1];
a == b;             // false
a === b;            // false
a === a;            // true

    What the interviewer checks: The interviewer checks whether you understand type conversion, safe equality checks, and object references.

    Other ways it was asked
    • “What is the difference between `==` and `===` in JavaScript?”
    • “What is the difference between the == and === operators in JavaScript?”
    • “In PHP, what is the difference between == and ===?”

  14. What are the four pillars of object-oriented programming?

    Asked in 5 of 267 interviews · last asked Oct 22 · Concept · Junior

    Show answer

    The four pillars are encapsulation, abstraction, inheritance, and polymorphism. Encapsulation keeps data and related methods together and controls access to internal state. Abstraction exposes essential operations while hiding implementation details. Inheritance lets a class build on another class, while polymorphism lets different object types respond differently to the same operation.

    • Encapsulation helps protect data from invalid changes.
    • Abstraction defines what an object does without exposing how it works.
    • Inheritance models an “is-a” relationship, such as a circle being a shape.
    • Polymorphism lets shared code work with different implementations through a common interface.
    Code
    Encapsulation: Circle keeps its radius private and rejects negative values.
Abstraction: Shape defines area() without requiring callers to know the calculation.
Inheritance: Circle and Rectangle extend Shape.
Polymorphism: Calling area() on either shape uses that shape’s calculation.

    What the interviewer checks: The interviewer checks whether you can explain each pillar and show how they differ.

    Other ways it was asked
    • “What is object-oriented programming?”
    • “What are the main principles of object-oriented programming?”
    • “What are the core concepts of object-oriented programming?”

  15. What is the difference between controlled and uncontrolled components in React?

    Asked in 5 of 267 interviews · last asked Oct 7 · Concept · Junior

    Show answer

    A controlled input gets its value from React state and updates that state through an event handler. An uncontrolled input keeps its value in the DOM, which you read with a ref or FormData. I use controlled inputs for live validation or linked fields. I use uncontrolled inputs for simple forms read on submit.

    • Controlled inputs use value or checked, usually with onChange.
    • Uncontrolled inputs use defaultValue or defaultChecked to set initial values.
    • Do not switch an input between controlled and uncontrolled during its lifetime.

    What the interviewer checks: The interviewer checks whether you understand who owns the input value and when each approach fits.

    Other ways it was asked
    • “What are controlled and uncontrolled components in React, and when would you use each?”
    • “Can you explain controlled and uncontrolled components in React?”
    • “What are controlled and uncontrolled components?”

  16. What is the virtual DOM in React?

    Asked in 5 of 267 interviews · last asked Oct 21 · Concept · Junior

    Show answer

    The virtual DOM is an in-memory description of the UI that React uses to work out updates. The real DOM is the browser’s tree of page elements. React compares the new description with the previous one, then applies needed changes to the real DOM. This helps manage updates, but does not guarantee better performance.

    • Comparing old and new UI descriptions is part of reconciliation.
    • Rendering a component does not always cause a real DOM change.
    • Stable keys help React match list items across renders.
    • Virtual DOM comparisons add work; they are not always faster than direct DOM updates.

    What the interviewer checks: The interviewer is checking whether you understand how React updates the page and the limits of its performance benefits.

    Other ways it was asked
    • “Why does React use a virtual DOM?”
    • “What are the DOM and Virtual DOM in React?”
    • “What is the virtual DOM in React, and how does it impact rendering performance?”

  17. What is the difference between the HTTP PUT and PATCH methods?

    Asked in 5 of 267 interviews · last asked Oct 7 · Concept · Junior

    Show answer

    PUT replaces a resource’s state with the supplied representation. PATCH applies changes to part of a resource. PUT is idempotent: repeating the same request has the same intended effect as sending it once. PATCH is not always idempotent; it depends on the changes requested.

    • PUT can also create a resource at the target URL if the server allows it.
    • PATCH setting a value can be idempotent; PATCH incrementing a value is not.
    • POST usually creates a resource or triggers an action and is not inherently idempotent.

    What the interviewer checks: The interviewer checks whether you understand replacement, partial updates, and the effect of repeating requests.

    Other ways it was asked
    • “What is the difference between PUT and PATCH?”
    • “What is the difference between the PUT and PATCH methods?”
    • “What is the difference between the PUT and PATCH HTTP methods?”

  18. In ASP.NET Core, what's the difference between transient, scoped, and singleton lifetimes?

    Asked in 5 of 267 interviews · last asked Sep 18 · Concept · Mid-level

    Show answer

    Transient creates a new instance each time the service is requested. Scoped creates one instance per scope, usually one HTTP request. Singleton creates one instance for the lifetime of the application’s service provider. A DbContext is normally scoped and not thread-safe, so injecting it directly into a singleton gives it the wrong lifetime and risks unsafe concurrent use.

    • Use transient for lightweight, independent services and scoped for request-level work.
    • Use singleton for shared services designed for concurrent use.
    • Singletons must not hold scoped services; scope validation can reject this dependency.
    • For singleton database work, create a scope per operation or use IDbContextFactory, and dispose the context.

    What the interviewer checks: The interviewer checks whether you can choose safe lifetimes and avoid sharing request-level state across requests.

    Other ways it was asked
    • “Explain transient, scoped, and singleton lifetimes in ASP.NET Core.”
    • “What is the difference between transient, scoped, and singleton lifetimes in ASP.NET Core dependency injection, and why should a DbContext not be injected directly into a singleton?”
    • “In .NET, what are the singleton, scoped, and transient service lifetimes, and when are they used?”

  19. What are microservices, and when would you choose them over a monolith?

    Asked in 5 of 267 interviews · last asked Sep 8 · Concept · Mid-level

    Show answer

    Microservices split an application into small services that can be deployed separately and communicate over a network. I would choose them when teams need independent releases or parts of the system need different scaling. For a small team or a new product, I would usually start with a monolith because it is simpler to build, test, and run.

    • Split services by business responsibility, not just technical layers.
    • Weigh team size, system complexity, scaling needs, and release speed.
    • Network calls add delays and failures; data consistency across services is harder.
    • Microservices need reliable deployment tools, monitoring, and clear service ownership.

    What the interviewer checks: The interviewer is checking whether you can explain microservices and justify their extra complexity for a real project.

    Other ways it was asked
    • “What is microservices architecture, and when would you use it?”
    • “What is a microservices architecture, and when would you use one?”
    • “What are microservices?”

  20. What is the difference between require and import in Node.js?

    Asked in 4 of 267 interviews · last asked Oct 19 · Concept · Junior

    Show answer

    require() loads modules synchronously using CommonJS; import is ES module syntax. Static imports are linked before code runs, while require() can run inside a condition or function. Dynamic import() works in both module systems and returns a promise.

    • CommonJS exports with module.exports; ES modules use export and export default.
    • Static import declarations must be at the module’s top level.
    • Use .cjs for CommonJS, .mjs for ES modules, or package.json’s type field to configure .js files.
    • Newer Node.js versions can require ES modules only when their dependency graph has no top-level await.
    JavaScript
    // CommonJS file: app.cjs
const fs = require('node:fs');

// ES module file: app.mjs
import fs from 'node:fs';

    What the interviewer checks: The interviewer checks whether you understand module syntax, loading behavior, and Node.js module support.

    Other ways it was asked
    • “Could you clarify the syntax differences between require and import, and explain how their loading mechanisms affect module behavior in Node.js?”
    • “What is the difference between `require` and `import` in Next.js?”
    • “Can you explain how require and import differ in syntax and when each is supported in Node.js?”

Programming fundamentals and coding interview questions

Check your language basics, object-oriented programming, data structures, algorithms, and understanding of processes and threads. 294 questions.

  1. Explain hoisting in JavaScript.

    Asked in 3 of 267 interviews · last asked Oct 21 · Concept · Junior

    Other ways it was asked
    • “What is hoisting in JavaScript?”
    • “Can you explain hoisting in JavaScript?”

  2. In Node.js, what's the practical difference between the event loop's microtask queue (Promises and queueMicrotask) and macrotask queue (setTimeout and setImmediate), and when would you choose one over the other?

    Asked in 3 of 267 interviews · last asked Aug 11 · Concept · Senior

    Other ways it was asked
    • “In Node.js, what's the difference between the microtask queue (promises and process.nextTick) and the macrotask queue (setTimeout and setImmediate), and how can this affect production latency?”
    • “In JavaScript's event loop, how do microtasks (promises) and macrotasks (setTimeout) differ in scheduling, and what's the practical impact on execution order?”

  3. What is the difference between Promise.all and Promise.allSettled?

    Asked in 3 of 267 interviews · last asked Oct 7 · Concept · Mid-level

    Other ways it was asked
    • “How do `Promise.all`, `Promise.race`, `Promise.allSettled`, and `Promise.any` differ?”

  4. What is JavaScript?

    Asked in 3 of 267 interviews · last asked Sep 24 · Concept · Junior

  5. What is a callback function, and what is it used for?

    Asked in 3 of 267 interviews · last asked Aug 20 · Concept · Junior

    Other ways it was asked
    • “Can you explain what a callback function is?”
    • “What is a callback function in Node.js?”

  6. What is the difference between a list and a tuple in Python?

    Asked in 2 of 267 interviews · last asked Jun 27 · Concept · Junior

  7. What is the difference between IEnumerable and IQueryable in .NET?

    Asked in 2 of 267 interviews · last asked Sep 1 · Concept · Mid-level

    Other ways it was asked
    • “What's the difference between IEnumerable and IQueryable?”
    • “In Entity Framework, what’s the difference between IEnumerable and IQueryable, and why do you care?”

  8. What is the difference between StringBuffer and StringBuilder?

    Asked in 2 of 267 interviews · last asked Jun 12 · Concept · Junior

    Other ways it was asked
    • “What is the difference between StringBuilder and StringBuffer?”
    • “What is the difference between String and StringBuilder in Java?”

  9. What does TypeScript add on top of JavaScript, and what tooling benefits does it provide?

    Asked in 2 of 267 interviews · last asked Jul 20 · Concept · Junior

    Other ways it was asked
    • “Why use TypeScript, and what benefits does it offer?”
    • “Can you explain why TypeScript is useful and what tooling it adds?”
    • “What does TypeScript add to JavaScript, and why does that help with development?”

  10. What is the difference between `any`, `unknown`, and `never` in TypeScript?

    Asked in 2 of 267 interviews · last asked Oct 7 · Concept · Mid-level

    Other ways it was asked
    • “What is the difference between any and unknown in TypeScript?”

  11. How does hashing work in Java, and what role does hashCode() play?

    Asked in 2 of 267 interviews · last asked Sep 16 · Concept · Junior

    Other ways it was asked
    • “How does the hashCode() method work in Java?”
    • “What is hashing in Java?”
    • “What do you understand by hashing in Java?”

  12. What is Java?

    Asked in 2 of 267 interviews · last asked Jul 17 · Concept · Junior

Show 1 more

  1. What is a JavaScript Promise used for, and when would you use one?

    Asked in 2 of 267 interviews · last asked Sep 30 · Concept · Junior

    Other ways it was asked
    • “What are JavaScript Promise methods, and when would you use them?”
    • “When would you use JavaScript Promise methods?”
    • “What is a promise in JavaScript, and what are its possible states?”

HTML, CSS and browser interview questions

These questions cover HTML, CSS, the DOM, browser requests, responsive design, and browser performance. 101 questions.

  1. What is the difference between CSS `display: none` and `visibility: hidden`?

    Asked in 2 of 267 interviews · last asked Jun 18 · Concept · Junior

    Other ways it was asked
    • “What is the difference between `display: block` and `visibility: hidden` in CSS?”

  2. What is the DOM, and how does JavaScript interact with it?

    Asked in 2 of 267 interviews · last asked May 9 · Concept · Junior

    Other ways it was asked
    • “What is the DOM, and what is it used for in JavaScript?”
    • “What is the DOM used for in JavaScript?”
    • “What is the DOM in web development?”

  3. What is HTML?

    Asked in 2 of 267 interviews · last asked Oct 19 · Concept · Junior

  4. What is an iframe?

    Asked in 2 of 267 interviews · last asked Jun 18 · Concept · Junior

    Other ways it was asked
    • “What is the iframe tag?”

  5. What is WordPress?

    Asked in 2 of 267 interviews · last asked Aug 27 · Concept · Junior

  6. How do you add a comment in HTML?

    Asked in 2 of 267 interviews · last asked Oct 19 · Concept · Junior

    Other ways it was asked
    • “Could you specify the exact syntax or tags used to add a comment in HTML?”
    • “What are the exact delimiters used to add a comment in HTML?”

  7. What is the difference between CSS Flexbox and CSS Grid?

    Asked once · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What is the difference between Flexbox and CSS Grid?”

  8. What is CORS, and how does it affect cross-origin requests?

    Asked once · last asked Sep 16 · Concept · Mid-level

  9. How would you improve frontend performance?

    Asked once · last asked Jul 30 · Scenario · Mid-level

  10. When uploading a file through a form, what attributes are needed on the form tag?

    Asked once · last asked May 9 · Concept · Junior

  11. What is the difference between visibility: hidden, display: none, and display: block?

    Asked once · last asked May 9 · Concept · Junior

  12. A user clicks the submit button on a website form, but nothing happens—there's no error message or success response. What are the first three things you would check?

    Asked once · last asked May 20 · Scenario · Mid-level

Show 8 more

  1. What are some of the new features introduced in HTML5 that enhance web application development?

    Asked once · last asked May 23 · Concept · Junior

  2. Can you elaborate on how you would use the Canvas element in a real-world project, and what kinds of applications could benefit from it?

    Asked once · last asked May 23 · Tooling · Junior

  3. What specific techniques do you use to achieve responsiveness in web design?

    Asked once · last asked May 23 · Concept · Junior

  4. What's the difference between Wix Editor and Editor X/Studio, and when would you choose each for a client project?

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

  5. When migrating a classic Wix Editor site to Studio/Editor X, what key limitations or risks do you validate first before committing?

    Asked once · last asked Jul 16 · Scenario · Senior

  6. How do you decide whether to use Velo versus no-code Wix features for a senior-level build?

    Asked once · last asked Jul 16 · Scenario · Senior

  7. How would you troubleshoot a customer report that downloads work in Chrome but fail in Safari, and what key details would you collect first?

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

  8. Which HTTP response headers and request details would you compare with Chrome to determine whether a Safari download failure involves CORS, Content-Disposition, MIME type, or cookies and sessions?

    Asked once · last asked Jul 16 · Scenario · Senior

All HTML and CSS interview questions

React, Angular and Next.js interview questions

Explore components, hooks, state, forms, rendering, and frontend architecture in React, Angular, Next.js, and other UI frameworks. 248 questions.

  1. What causes React components to render or rerender, including unnecessarily?

    Asked in 4 of 267 interviews · last asked Oct 2 · Concept · Mid-level

    Other ways it was asked
    • “What can cause excessive renders in a React application?”
    • “What can cause unnecessary re-renders in a React application?”
    • “How can you prevent unnecessary re-renders in a React application?”

  2. What is the difference between React and Next.js?

    Asked in 4 of 267 interviews · last asked Sep 8 · Concept · Junior

    Other ways it was asked
    • “How is Next.js different from React?”
    • “What are the advantages of a standard React application compared with a Next.js application?”
    • “What are the differences between Angular and Next.js?”

  3. What is Redux?

    Asked in 4 of 267 interviews · last asked Oct 15 · Concept · Junior

    Other ways it was asked
    • “What is Redux, and how is it used with React?”
    • “What is Redux Toolkit?”
    • “What benefits does Redux provide, and why is it used?”

  4. What is a component in React?

    Asked in 4 of 267 interviews · last asked Sep 10 · Concept · Junior

    Other ways it was asked
    • “What is a component?”
    • “What are components in React?”

  5. What are the differences between useEffect, useMemo, and useCallback?

    Asked in 3 of 267 interviews · last asked Sep 18 · Concept · Mid-level

    Other ways it was asked
    • “What is the difference between useMemo and useCallback?”
    • “When would you use useEffect, useMemo, and useCallback in a React application?”

  6. How do static site generation and server-side rendering differ in Next.js, and when would you use each?

    Asked in 3 of 267 interviews · last asked Oct 7 · Concept · Mid-level

    Other ways it was asked
    • “What is the difference between SSR and SSG in Next.js?”
    • “What is the difference between SSG and SSR in Next.js?”
    • “What is static site generation in Next.js, and when would you use it?”

  7. What are props and state in React, and what is the difference between them?

    Asked in 3 of 267 interviews · last asked Oct 15 · Concept · Junior

    Other ways it was asked
    • “What is the difference between state and props?”
    • “What is the difference between props and state in React?”
    • “What are state and props?”

  8. What are Angular signals, and how are they used?

    Asked in 2 of 267 interviews · last asked Oct 15 · Concept · Mid-level

    Other ways it was asked
    • “Why are Angular signals used?”
    • “What are the advantages of using Angular signals?”
    • “What are signals in Angular?”

  9. How do Angular and React differ, and how would you choose between them?

    Asked in 2 of 267 interviews · last asked Sep 14 · Concept · Mid-level

    Other ways it was asked
    • “What is the difference between Angular and React?”
    • “Can you tell me the difference between Angular and React.js?”

  10. How do you pass data from a parent component to a child component in Angular?

    Asked in 2 of 267 interviews · last asked Sep 29 · Concept · Junior

    Other ways it was asked
    • “How do you pass data between components in Angular?”
    • “How do you pass data between Angular components that have no parent-child relationship?”
    • “How do you send data from a child component to a parent component in React?”

  11. What is the difference between functional components and class components in React?

    Asked in 2 of 267 interviews · last asked May 31 · Concept · Junior

    Other ways it was asked
    • “What is the difference between functional components and class components?”
    • “What is a React component, and what are class-based and function-based components?”

  12. Could you explain what each function does and when you'd use getStaticProps versus getServerSideProps?

    Asked in 2 of 267 interviews · last asked Aug 20 · Concept · Mid-level

    Other ways it was asked
    • “What is the purpose of getStaticProps and getServerSideProps?”
Show 2 more

  1. What are the different ways to manage state in a React application?

    Asked in 2 of 267 interviews · last asked Jul 16 · Concept · Mid-level

    Other ways it was asked
    • “How do you manage component state in a React application?”
    • “What state management solutions are available in React?”

  2. When should you use React performance hooks such as useMemo and useCallback, and when can they hurt?

    Asked in 2 of 267 interviews · last asked Jul 16 · Scenario · Senior

    Other ways it was asked
    • “Since excessive use of useMemo and useCallback can become a bottleneck, how do you decide when to use them and avoid slowing down the application?”
    • “How would you identify and resolve a performance issue related to excessive useMemo or useCallback, and decide whether to remove them?”
    • “Which React Hooks can help improve performance, and when would you use them?”

All React interview questions

Backend API and security interview questions

Work through backend frameworks, dependency injection, middleware, REST, GraphQL, authentication, authorization, and customer data security. 254 questions.

  1. How is GraphQL different from REST?

    Asked in 4 of 267 interviews · last asked Sep 22 · Concept · Mid-level

    Other ways it was asked
    • “What are the differences between GraphQL and REST?”
    • “What problem does GraphQL solve compared with REST APIs?”
    • “What is the difference between GraphQL and REST?”

  2. Where should you store JWTs in a single-page application, and how do you keep them secure?

    Asked in 4 of 267 interviews · last asked Oct 10 · Scenario · Senior

    Other ways it was asked
    • “How would you securely handle JWTs in a frontend application?”
    • “How can you securely handle JWT authentication tokens in a single-page application?”
    • “Where is the JWT token stored?”

  3. What is a REST API?

    Asked in 4 of 267 interviews · last asked Aug 27 · Concept · Junior

    Other ways it was asked
    • “What are REST APIs, and when would you use them?”

  4. What is JWT authentication?

    Asked in 4 of 267 interviews · last asked Sep 16 · Concept · Junior

    Other ways it was asked
    • “What are JWTs, and how can you use them to authenticate an application?”
    • “Explain JWT authentication.”
    • “What is a JWT, and how does it work?”

  5. What is middleware, and how is it used in an application?

    Asked in 4 of 267 interviews · last asked Jul 17 · Concept · Junior

    Other ways it was asked
    • “What is middleware in a web application?”
    • “What is middleware, and what does it do?”
    • “What is middleware?”

  6. What do you consider when designing a REST API?

    Asked in 4 of 267 interviews · last asked Jul 29 · Concept · Mid-level

    Other ways it was asked
    • “How do you design and develop a RESTful API?”
    • “What factors do you consider when designing or consuming REST APIs?”
    • “How do you design REST APIs?”

  7. What is Node.js? Explain it.

    Asked in 4 of 267 interviews · last asked Aug 27 · Concept · Junior

    Other ways it was asked
    • “What is Node.js?”
    • “Can you explain what Node.js is?”

  8. What is middleware in ASP.NET Core?

    Asked in 3 of 267 interviews · last asked Sep 18 · Concept · Junior

    Other ways it was asked
    • “What is .NET Core middleware?”

  9. What is the difference between GET and POST?

    Asked in 3 of 267 interviews · last asked Aug 20 · Concept · Junior

    Other ways it was asked
    • “What is the difference between GET and POST methods in PHP?”
    • “What is the difference between PUT and POST in REST APIs?”

  10. What is .NET Core?

    Asked in 3 of 267 interviews · last asked Oct 15 · Concept · Junior

    Other ways it was asked
    • “What is the difference between .NET Framework and .NET Core?”

  11. How do you secure a REST API?

    Asked in 2 of 267 interviews · last asked Jul 16 · Scenario · Senior

    Other ways it was asked
    • “How do you secure an API?”
    • “How do you ensure API security beyond authentication, for example, when handling sensitive data?”

  12. How would you prevent one customer's data from being exposed to another customer in a multitenant system?

    Asked in 2 of 267 interviews · last asked Sep 1 · Scenario · Senior

    Other ways it was asked
    • “How would you handle tenant isolation so customer data doesn’t leak across tenants?”
Show 4 more

  1. Can you explain what middleware is in Express.js and give some examples?

    Asked in 2 of 267 interviews · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What are some examples of external middleware used in Express.js applications?”
    • “How does middleware work in Express, and what kinds of tasks are appropriate to implement as middleware?”

  2. How would you implement authentication using JWT in a React application?

    Asked in 2 of 267 interviews · last asked Sep 9 · Tooling · Mid-level

    Other ways it was asked
    • “How would you securely store a JWT in a React application?”

  3. How do you structure a Node.js backend project, including controllers, models, and database connections?

    Asked in 2 of 267 interviews · last asked Sep 13 · Design · Mid-level

    Other ways it was asked
    • “How do you structure your Node.js backend?”

  4. How do you authenticate an API?

    Asked in 2 of 267 interviews · last asked Sep 19 · Concept · Junior

    Other ways it was asked
    • “How does authentication work in an API?”

SQL and NoSQL database interview questions

Database questions cover SQL and NoSQL choices, data models, queries, indexes, transactions, ORMs, and query performance. 184 questions.

  1. What is the N+1 query problem, and how can you avoid it?

    Asked in 4 of 267 interviews · last asked Oct 7 · Concept · Mid-level

    Other ways it was asked
    • “How can you avoid the N+1 query problem?”
    • “What is the N+1 query problem, and how do you fix it?”
    • “What is the N+1 query problem, and how would you identify and address it?”

  2. Do you know the difference between clustered and non-clustered indexes in SQL Server?

    Asked in 4 of 267 interviews · last asked Oct 10 · Concept · Mid-level

    Other ways it was asked
    • “In SQL, what is the difference between clustered and nonclustered indexes?”
    • “What is the difference between clustered and nonclustered indexes?”
    • “What's the difference between a clustered and a non-clustered index?”

  3. What are database indexes, and when would you use them?

    Asked in 3 of 267 interviews · last asked Aug 26 · Concept · Junior

    Other ways it was asked
    • “What are database indexes?”
    • “What is a database index?”
    • “What is indexing?”

  4. What is the difference between a full outer join, a left outer join, and an inner join?

    Asked in 3 of 267 interviews · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What is the difference between inner, left, and right joins?”
    • “How do `INNER JOIN`, `LEFT JOIN`, `RIGHT JOIN`, and `FULL OUTER JOIN` differ?”
    • “What is the difference between INNER JOIN and OUTER JOIN, and how does LEFT JOIN fit in?”

  5. What does UNION do in SQL, and how does it differ from UNION ALL?

    Asked in 3 of 267 interviews · last asked Aug 12 · Concept · Junior

    Other ways it was asked
    • “What is the difference between UNION and UNION ALL?”
    • “What is the use of `UNION`?”
    • “What is the use of union and union all?”

  6. What is database normalization?

    Asked in 3 of 267 interviews · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What is database normalization, and why is it needed?”

  7. How would you optimize a slow-running SQL query?

    Asked in 2 of 267 interviews · last asked Sep 29 · Scenario · Mid-level

    Other ways it was asked
    • “What can you do to improve the performance of a slow SQL query?”
    • “How do you handle and improve a slow-running query?”

  8. What are the disadvantages of database indexes?

    Asked in 2 of 267 interviews · last asked Jul 16 · Concept · Mid-level

    Other ways it was asked
    • “What are the drawbacks of using database indexes?”
    • “What are the advantages and trade-offs of database indexes?”

  9. How would you design users, roles, and matching at the database level?

    Asked in 2 of 267 interviews · last asked Jul 22 · Design · Mid-level

  10. What are the differences between the code-first and database-first approaches in Entity Framework, and when would you use each?

    Asked in 2 of 267 interviews · last asked Oct 9 · Concept · Mid-level

    Other ways it was asked
    • “What are the differences between code-first and database-first approaches in Entity Framework Core?”

  11. What does the ACID acronym stand for in database transactions?

    Asked in 2 of 267 interviews · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What are the ACID properties in database transactions?”
    • “What is a database transaction, what does ACID mean, and can you give an example of when a transaction is necessary?”

  12. What is a database?

    Asked in 2 of 267 interviews · last asked Aug 26 · Concept · Junior

Show 7 more

  1. What are aggregate functions? Can you give an example?

    Asked in 2 of 267 interviews · last asked May 10 · Concept · Junior

    Other ways it was asked
    • “What is an aggregate function, and can you name a few commonly used aggregate functions in MySQL?”

  2. What is an ORM?

    Asked in 2 of 267 interviews · last asked Jul 30 · Concept · Junior

    Other ways it was asked
    • “What is an ORM? Can you name one?”
    • “What is ORM?”

  3. What types of relationships can exist between database tables?

    Asked in 2 of 267 interviews · last asked Oct 7 · Concept · Junior

    Other ways it was asked
    • “What other types of relationships can exist between database tables?”

  4. What is the _id field in MongoDB?

    Asked in 2 of 267 interviews · last asked Sep 15 · Concept · Junior

    Other ways it was asked
    • “What is the purpose of the _id field in a MongoDB document?”

  5. What's the difference between WHERE and HAVING?

    Asked once · last asked Aug 5 · Concept · Junior

    Other ways it was asked
    • “What is the difference between WHERE and HAVING?”

  6. Write a SQL query to find the second-highest salary.

    Asked once · last asked Aug 22 · Write code · Junior

    Other ways it was asked
    • “Can you write a SQL query to find the second-highest salary?”

  7. What is the difference between a primary key and a unique constraint?

    Asked once · last asked Aug 12 · Concept · Junior

    Other ways it was asked
    • “What is the difference between a primary key and a unique key?”

All SQL interview questions

Full stack system design interview questions

Think through architecture, design patterns, distributed systems, messaging, scaling, cloud infrastructure, reliability, and production troubleshooting. 302 questions.

  1. Can you explain the SOLID principles?

    Asked in 4 of 267 interviews · last asked Sep 28 · Concept · Mid-level

    Other ways it was asked
    • “Can you explain a bit more about what each SOLID principle means?”
    • “What are the SOLID principles?”
    • “What do the SOLID principles mean?”

  2. What is the MVC architecture?

    Asked in 4 of 267 interviews · last asked Jul 16 · Concept · Junior

    Other ways it was asked
    • “What is MVC?”
    • “Explain MVC.”
    • “What's the purpose of MVC architecture?”

  3. How would you design a payment processing system?

    Asked in 3 of 267 interviews · last asked Oct 7 · Design · Mid-level

    Other ways it was asked
    • “How would you implement payment processing?”
    • “How would you implement payment processing in an application?”

  4. What is the difference between horizontal and vertical scaling, and when would you use each?

    Asked in 2 of 267 interviews · last asked Sep 8 · Concept · Mid-level

    Other ways it was asked
    • “What is the difference between vertical and horizontal scaling?”
    • “What is the biggest difference between horizontal scaling and vertical scaling?”

  5. What is domain-driven design, and when would you use it?

    Asked in 2 of 267 interviews · last asked Sep 28 · Concept · Senior

    Other ways it was asked
    • “What is domain-driven design (DDD), and in what situations is it particularly useful?”

  6. If an API suddenly goes slow in production and customers start complaining, what’s your step-by-step approach?

    Asked in 2 of 267 interviews · last asked Sep 1 · Scenario · Senior

    Other ways it was asked
    • “Imagine a production API is slow and users are complaining. What's your step-by-step approach to investigate?”
    • “If an API is slow in production, what do you do first and how do you proceed?”

  7. What is the difference between synchronous and asynchronous communication between services?

    Asked in 2 of 267 interviews · last asked Oct 9 · Concept · Mid-level

    Other ways it was asked
    • “How would you decide whether to use synchronous or asynchronous communication between services?”

  8. Which design patterns are you familiar with?

    Asked in 2 of 267 interviews · last asked Jun 12 · Concept · Mid-level

    Other ways it was asked
    • “Which design patterns do you know, and when do you apply them?”

  9. What do you mean by a class diagram?

    Asked in 2 of 267 interviews · last asked Mar 27 · Concept · Junior

  10. How would you use MVC and hexagonal architecture, and how do they differ?

    Asked once · last asked Sep 16 · Concept · Mid-level

    Other ways it was asked
    • “Why would you choose hexagonal architecture over MVC?”
    • “Can hexagonal architecture be implemented using MVC?”

  11. What are the differences between Kafka and RabbitMQ?

    Asked once · last asked Sep 16 · Concept · Mid-level

    Other ways it was asked
    • “What is the key difference between Kafka and RabbitMQ?”
    • “How would you decide whether to use Kafka or RabbitMQ for an application?”

  12. How would you ensure reliable data synchronization between MongoDB and OpenSearch?

    Asked once · last asked Sep 7 · Design · Senior

    Other ways it was asked
    • “How would you minimize synchronization delays between MongoDB and OpenSearch?”
    • “How would you design reliable synchronization between MongoDB, OpenSearch, and APIs?”
Show 7 more

  1. How would you approach designing and building a transactional platform for a fintech business?

    Asked once · last asked Apr 11 · Design · Mid-level

    Other ways it was asked
    • “How would you estimate the cost of building a transactional platform for a fintech business?”

  2. What causes cold starts in AWS Lambda, and how can they be mitigated?

    Asked once · last asked Oct 8 · Concept · Mid-level

  3. What is hexagonal architecture, and how does it structure an application?

    Asked once · last asked Sep 16 · Concept · Mid-level

    Other ways it was asked
    • “Can you give a small example of how hexagonal architecture separates an application’s components?”

  4. What are the key considerations when designing a microservices architecture?

    Asked once · last asked May 14 · Design · Senior

  5. Where should secrets be stored when packaging a development environment with Docker?

    Asked once · last asked Jul 28 · Tooling · Mid-level

    Other ways it was asked
    • “Where should secrets be stored in a Dockerized development environment, and how should they be changed at runtime?”

  6. If a website is slow, how would you troubleshoot it and find the root cause?

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

    Other ways it was asked
    • “What steps would you take to find the root cause of slowness on a website?”

  7. How would you design rate limiting for a public API?

    Asked once · last asked Sep 13 · Design · Senior

    Other ways it was asked
    • “How would you implement a rate limiter for APIs?”

Software testing and CI/CD interview questions

Review unit and integration tests, mocking, quality checks, Git workflows, deployment pipelines, and release validation. 105 questions.

  1. How would you design a CI/CD pipeline?

    Asked in 2 of 267 interviews · last asked Oct 8 · Design · Mid-level

    Other ways it was asked
    • “What are the main stages of a CI/CD pipeline?”
    • “How do you implement a CI/CD pipeline, and how does it work?”

  2. How do you ensure the quality of the code your team delivers?

    Asked in 2 of 267 interviews · last asked Jun 26 · Behavioral · Senior

    Other ways it was asked
    • “How do you ensure the quality of the team's work and code?”
    • “How do you ensure code quality while working in a fast-paced environment?”

  3. What is unit testing?

    Asked in 2 of 267 interviews · last asked Mar 27 · Concept · Junior

    Other ways it was asked
    • “What do you mean by unit testing?”

  4. What is GitHub?

    Asked in 2 of 267 interviews · last asked Aug 27 · Concept · Junior

  5. Can you compare black-box and white-box testing?

    Asked once · last asked Mar 27 · Concept · Junior

    Other ways it was asked
    • “What is the difference between black-box and white-box testing?”

  6. How would you test a function that makes an external API call?

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

    Other ways it was asked
    • “Can you write a unit test for a function that makes an external API call?”

  7. How would you decide which CI/CD steps to adjust first, and how would you measure improvements in release repeatability?

    Asked once · last asked Sep 21 · Behavioral · Senior

    Other ways it was asked
    • “How did you decide which CI/CD steps to adjust first, and how did you measure improvements in release repeatability?”
    • “How did you decide which CI/CD steps to adjust first, and how did you validate each change?”

  8. How do you manage the Git workflow for a new feature from development through the different environments to production?

    Asked once · last asked Feb 10 · Scenario · Senior

  9. How does a feature or production fix move from requirements gathering through deployment?

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

  10. How can the same build artifact be promoted automatically through successive environments without rebuilding it at each stage?

    Asked once · last asked Feb 26 · Tooling · Mid-level

  11. How do you contribute to production deployments, and how do you coordinate with a separate team responsible for the final release?

    Asked once · last asked Feb 26 · Behavioral · Mid-level

  12. How would you resolve a merge conflict in Git?

    Asked once · last asked Feb 27 · Scenario · Mid-level

Show 8 more

  1. How do you manage end-to-end testing when an application consists of many services that must be started or kept running?

    Asked once · last asked Mar 19 · Scenario · Senior

  2. How would you handle challenges across the different phases of a cloud-based project pipeline?

    Asked once · last asked Mar 24 · Behavioral · Mid-level

    Other ways it was asked
    • “What challenges did you encounter during the different phases of a cloud-based project pipeline?”

  3. How would you handle environment-specific configurations when deploying with Vercel or Render?

    Asked once · last asked Apr 9 · Tooling · Mid-level

  4. When working with Git and GitHub, how do you typically structure branches for a team working on features?

    Asked once · last asked Apr 9 · Tooling · Mid-level

  5. What governance processes do you use? Do you conduct code reviews and quality checks, and what are your quality gates?

    Asked once · last asked May 5 · Scenario · Senior

  6. How do you handle code reviews, and what do you focus on when giving feedback or reviewing someone else's work?

    Asked once · last asked May 11 · Behavioral · Mid-level

  7. How could you let a prospect try a requested feature without releasing it to all customers?

    Asked once · last asked Jun 2 · Scenario · Senior

  8. What other approaches could isolate a feature from the rest of a release so existing customers are unaffected?

    Asked once · last asked Jun 2 · Scenario · Senior

AI and machine learning interview questions for developers

AI questions cover coding tools, agents, RAG, LLM privacy and costs, recommendation systems, and machine-learning evaluation. 93 questions.

  1. What are AI agents, and when would you use them?

    Asked in 3 of 267 interviews · last asked Oct 16 · Concept · Mid-level

    Other ways it was asked
    • “What are AI agent skills, and when would you use them?”
    • “How do you use AI agents?”
    • “What are AI agents, and how can they be used in a software development workflow, particularly for coding?”

  2. What are the main components of a RAG system?

    Asked in 3 of 267 interviews · last asked Sep 30 · Concept · Mid-level

    Other ways it was asked
    • “What is RAG?”
    • “What is a RAG system, and when would you use one?”
    • “What problems can a RAG system address, and why would you implement one?”

  3. How would you implement a retrieval-augmented generation (RAG) system?

    Asked in 2 of 267 interviews · last asked Sep 30 · Design · Mid-level

    Other ways it was asked
    • “How does a retrieval-augmented generation (RAG) system work, step by step?”
    • “How are you implementing a retrieval-augmented generation (RAG) system?”

  4. What is a recommendation system?

    Asked in 2 of 267 interviews · last asked Sep 28 · Concept · Junior

    Other ways it was asked
    • “How does a recommendation system work?”

  5. How is OCR integration used in an application?

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

    Other ways it was asked
    • “What is OCR integration?”

  6. When would you use supervised rather than unsupervised learning for a recommendation model?

    Asked once · last asked Sep 28 · Concept · Mid-level

    Other ways it was asked
    • “How would you use supervised learning to train a recommendation model?”
    • “Why might supervised learning be a better choice than unsupervised learning for a recommendation model?”
    • “How do supervised learning and reinforcement learning differ when building a recommendation model?”

  7. How do you evaluate the quality of AI-generated code before using it?

    Asked once · last asked Aug 10 · Scenario · Senior

    Other ways it was asked
    • “What are the potential pitfalls you have encountered with AI-generated code, and how do you ensure the quality of the code generated?”

  8. How would you build an AI agent?

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

    Other ways it was asked
    • “What components are needed to build an AI agent?”

  9. How would you organize shared AI coding assistant resources in repositories so a team can maintain and improve them over time?

    Asked once · last asked Aug 31 · Tooling · Mid-level

    Other ways it was asked
    • “How would you organize AI coding assistant skills in a shared repository for team use?”

  10. When would you prefer precision over recall?

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

    Other ways it was asked
    • “When would you prefer recall over precision?”

  11. How do you measure whether feature engineering changes improve a machine-learning model?

    Asked once · last asked Oct 16 · Concept · Mid-level

  12. How do you keep Markdown documentation up to date when features change, and can AI help maintain it?

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

Show 7 more

  1. What is supervised machine learning, and how are training and test data used?

    Asked once · last asked Mar 24 · Concept · Junior

  2. How can AI hallucinations be reduced, and why might you use RAG to address them?

    Asked once · last asked Apr 17 · Concept · Senior

  3. How are you using AI to improve software product quality?

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

  4. How do you use Antigravity and Claude in your projects?

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

  5. How would you use feedback to help an AI agent avoid repeating incorrect results?

    Asked once · last asked Jun 25 · Scenario · Senior

  6. What approvals or consent should you obtain before using AI with customer data?

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

  7. How would you manage token limits when an AI application runs out of available tokens?

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

Full stack developer behavioral and project interview questions

Use these questions to explain project ownership, estimates, priorities, teamwork, stakeholder communication, product metrics, and experiments. 162 questions.

  1. What tools would you use for A/B testing?

    Asked in 2 of 267 interviews · last asked Oct 16 · Scenario · Mid-level

    Other ways it was asked
    • “How do you conduct an A/B test?”
    • “How have you used A/B testing, and how did you evaluate the results?”
    • “How would you design a minimal A/B test?”

  2. Tell me about a recent project where you personally took a feature from idea through production.

    Asked in 2 of 267 interviews · last asked Sep 18 · Behavioral

    Other ways it was asked
    • “Tell me about a recent project where you took a feature from identifying a problem through production. What decisions did you make, and how did you know the feature worked?”

  3. How do you bring structure to a chaotic project?

    Asked in 2 of 267 interviews · last asked May 11 · Scenario · Mid-level

    Other ways it was asked
    • “How do you typically handle a work environment that isn't very organized, and how do you bring structure to a chaotic project?”

  4. How do you estimate project timelines?

    Asked in 2 of 267 interviews · last asked Jul 22 · Scenario · Mid-level

  5. If you had one more day to improve a software project, what would you prioritize?

    Asked in 2 of 267 interviews · last asked Oct 12 · Scenario

    Other ways it was asked
    • “How would you prioritize improvements to an application if you had one additional week?”

  6. How do you estimate work using story points?

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

    Other ways it was asked
    • “How do you estimate work in Scrum, using story points or another approach?”

  7. How do you explain technical architecture and decisions to technical and non-technical clients?

    Asked once · last asked Sep 14 · Behavioral · Senior

    Other ways it was asked
    • “How would you explain a technical architecture and its cost to a non-technical client?”
    • “How do you explain technical architecture and technology choices to both technical and non-technical clients?”

  8. What is the most technically challenging feature you've had to build, and why was it challenging?

    Asked once · last asked May 20 · Behavioral · Mid-level

  9. How would you measure whether changes to a booking flow improved its reliability or performance?

    Asked once · last asked Sep 21 · Scenario · Mid-level

    Other ways it was asked
    • “How did you measure the reliability of a booking flow after making a change?”

  10. Why do Agile teams use story points instead of estimating work directly in hours?

    Asked once · last asked Sep 30 · Concept · Mid-level

  11. Tell us about a product feature or piece of code you implemented that you’re proud of. Why does it stand out, and what challenges did you overcome during implementation?

    Asked once · last asked Feb 11 · Behavioral

  12. If a technical lead or architect gives you a direction to follow but can’t explain the reason behind it, and their approach differs from how you would solve the problem, how would you handle the situation and decide how to move forward?

    Asked once · last asked Feb 11 · Scenario · Senior

Show 8 more

  1. Can you share an example of how you optimized performance in one of your applications, and what specific strategies you used?

    Asked once · last asked Feb 25 · Behavioral · Mid-level

  2. What was the most significant technical debt you worked on?

    Asked once · last asked Feb 26 · Behavioral · Senior

  3. What do you know about Pantalon's Instant Influence model?

    Asked once · last asked Mar 17 · Concept · Mid-level

  4. What are Cialdini's six principles of social influence?

    Asked once · last asked Mar 17 · Concept · Junior

  5. What is the 5P model for leading young employees, and how can it be applied across different employee development levels?

    Asked once · last asked Mar 17 · Concept · Senior

  6. How do you make the case for addressing technical debt, and what outcomes have you achieved?

    Asked once · last asked Mar 19 · Behavioral · Senior

  7. How would you resolve a disagreement during a code review?

    Asked once · last asked Mar 19 · Scenario · Mid-level

  8. How do you communicate a necessary scope reduction to stakeholders?

    Asked once · last asked Mar 19 · Scenario · Mid-level

Live coding round next? Coding mode in the MeetAssist desktop app solves the problem on your screen, with your phone as the remote.

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 Full Stack Developer 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.

267 interviews, 172 candidates, Nov 2025 to Oct 2026. Updated every month with new interviews.