Frontend

Have you ever used discriminant unions and type guards? What built-in type guards do you know?

Were there many defects? Was there any challenge in optimizing forms? Why does React Hook Form work quickly with large forms — what is the optimization based on?

Have you worked with SWR? What were the nuances, issues with data relevance?

How do you save the state of a form (draft) upon page reload?

How often have you had to work with generics? Where have you used utility types: Pick, Omit, Partial, Record, ReturnType, Exclude?

How did you ensure the typing of API responses? Did you use OpenAPI/Swagger or code generation?

How closely have you worked with Next.js? What features do you use?

How to type components with HTML attributes and refs?

Are there areas you would like to improve?

What testing tools have you worked with? How were the tests integrated into CI?

Has the platform been used in the end? What feedback was received from users and support?

If you think about what you would like to do in the future — where does your desire and soul lean?

Did you use optimistic updates? Did you provide user indication during background data updates?

What are the similarities and differences between types and interfaces in TypeScript? When to use each?

What do you use for state management and what would you choose in a new project?

Was there code splitting in the project? Which bundler was used?

How to avoid call stack overflow when traversing a tree? How to implement iterative traversal using a stack in JavaScript?

How would you separate server and client state?

How to organize a schema for a multi-step form in Zod? How to handle conditional validation?

Tell me about a complex solution that you had to design from scratch and develop.