C#

Can you explain the concept of inheritance in object-oriented programming?

Data formats — JSON vs XML, differences, where are they used?

How have you implemented the Singleton pattern in your projects, and what nuances have you encountered?

At what point is C# code compiled into intermediate bytecode?

String in Go — what is it, how is it organized under the hood?

Explain the differences between the keywords async and await when working with asynchronous programming.

Can you explain what the ConfigureAwait method does in asynchronous programming and why it is needed?

Where inside a class is it best to store important data types?

What is your experience with PostgreSQL?

Explain the main difference between architectural patterns MVC and MVVM.

How long can the process of changing jobs to a new position take?

Junior — Middle

OZON

Explain the principles of operation and main features of Entity Framework Core as an ORM tool for .NET applications.

What criteria are used to determine which database columns should have indexes?

Task: you are asked to review the code of a new feature, which allows booking a tour (consisting of a flight ticket and a hotel). The features for separate booking of flight tickets and tours already exist, and this task expects a unified method that books the entire tour or nothing.

Middle+

OZON

What is a deadlock in the context of databases?

What relational and non-relational databases have you worked with? What were non-relational databases used for?

Tell me about indexes in databases — what they are, how to use them, and what types exist.

Can you explain what JWT is and how it is used in ASP.NET applications?

Task 1 Implement (without using LINQ) a method that returns an array without duplicates while preserving the order of elements. int[] Distinct(int[] src) //[1,2,5,3,3,2] → [1,2,5,3] -------------- insert solution below --------------

Middle+

Pyrus

What types of operations and commands can be performed in PostgreSQL?