Frontend

Tell about SSR, CSR, and SSG — what is the difference?

What is gRPC and what is it used for?

Tell about architectural approaches: FSD, modular monolith. Which architecture to choose for a small MVP?

How to handle a long asynchronous operation on the client side (virus scan, up to an hour)?

What are Pick and Omit in TypeScript?

What happens with display:none vs visibility:hidden in terms of reflow and repaint?

What are keyof and typeof in TypeScript?

Does changing a private method violate the Open/Closed principle?

// What will be printed to the console? const p1 = Promise.resolve(1); const p2 = new Promise((_, reject) => setTimeout(() => reject("Error"), 100)); const p3 = Promise.resolve(3); Promise.all([p1, p2, p3]) .then(console.log) .catch(console.error); Promise.allSettled([p1, p2, p3]).then(console.log);

```javascript console.log("Start"); setTimeout(() => { console.log("Timeout 1"); Promise.resolve().then(() => console.log("Promise inside Timeout")); }, 0); Promise.resolve() .then(() => { console.log("Promise 0"); setTimeout(() => console.log("Timeout inside Promise"), 0); }) .catch(() => console.log("Promise 1")) .then(() => console.log("Promise 2")); function foo() { Promise.resolve().then(() => { console.log("Promise 3"); foo(); }); } foo(); requestAnimationFrame(() => { console.log("RequestAnimationFrame"); }); console.log("End"); // Start // END // "Promise 0" // Promise 2 // // Timeout 1 // Promise inside Timeout // RequestAnimationFrame // Timeout inside Promise ```

What authentication and authorization protocols do you know? Tell me about JWT.

HTTP status codes: what do 401, 403, 500, 200, 201 mean?

What is the difference between REST and GraphQL?

Which CSS properties cause only Repaint, and which cause Reflow/Layout?

Tell about the principles of SOLID.

Where in the browser can data be stored on the client side?

What types of attacks on the frontend do you know? How to protect against them?

How does the refresh token mechanism work?

What is the difference between an arrow function and a regular function in JavaScript?

Tell me about SSE (Server-Sent Events) and compare it with WebSocket and polling.