Frontend

What blocking operations are there within the Critical Rendering Path?

How would you optimize a slow-running application? What methods would you use?

Live coding task: fix the counter with setInterval in useEffect, which works incorrectly due to closure issues.

What services are typically used at the application level (i.e., should be providedIn: 'root')?

Tell me more about caching for fast page delivery. Provide an example on the second interface (question screen).

Middle+

Okko

Are you aware of different versions of the HTTP protocol (HTTP/1, HTTP/2, HTTP/3)? What are the differences between them?

Middle+

Альфа-Банк

What do you look for in a future employer, what are your criteria for choosing?

Write a polyfill for the String startsWith method, which appeared in ES6, using only ES5 features (without let/const, arrow functions, etc.), i.e., through prototype inheritance.

How do you feel about logic in templates?

Middle

Рунити

What auxiliary tools, including tools for testing, refactoring, and code review, do you use?

Theoretically speaking: there are large tables with a lot of data. Can performance issues arise? If yes, how would you solve them?

Example with object filters (field name and others) - how to use reactive to track changes in individual properties?

How to get the value from a Promise and handle errors?

What is the difference between a client component and a server component in Next.js?

Explain the concept of declarative programming with respect to React.

Middle+

Andersen

interface FormState { values: FormValues; errors: FormErrors; isLoading: boolean; } const [formState, setFormState] = useState<FormState>({ values: { email: '', password: '', }, errors: {}, isLoading: false, });

What are WeakSet and WeakMap, and how do they differ from Set and Map?

How good is it generally to describe a function in a component that also returns JSX?

Implement a debounce function.

How is the interaction with the backend structured in your project — agreements on the API, where the request logic is stored (hooks, modules, etc.)?