Best Go Interview Questions To Ask Candidates

When it comes to hiring Go developers, the process becomes even more challenging due to the unique skill set and responsibilities associated with this programming language.

To help you navigate this intricate landscape, we have curated a list of 15 interview questions that will assist in identifying the best Go developers.

1. What are Goroutines, and how do they compare to threads?

Goroutines are a fundamental part of Go's approach to concurrency. A strong Go developer should be able to explain the concept and how it differs from traditional threading.

This understanding will give insights into the developer's knowledge of concurrent programming in Go.

2. What’s your experience with Go's concurrency model? Have you worked on projects that used goroutines and channels?

Understanding concurrency is crucial in modern software development as it enables the efficient use of resources.

Go has a unique approach to concurrency with goroutines and channels. A good candidate should be able to navigate this aspect of the language effectively.

3. Describe a situation where you had to optimize Go code for better performance.

Performance optimization is an important aspect of software development. A developer who can identify performance issues and has a methodology to improve them is very valuable.

This question will allow you to assess their problem-solving skills and their ability to improve the performance of their code.

4. How have you used Go's interfaces in your projects?

Go's type system, including interfaces, is a key aspect of the language. A Go developer should understand when and why to use interfaces to design more flexible, reusable code.

This question also helps assess the candidate's grasp of Go's type system and their ability to apply good design principles.

5. Can you explain how Go manages memory? How does the garbage collectior work in Go?

Memory management is a fundamental aspect of any programming language. Go has a built-in garbage collector, understanding how it works can influence how you write Go code.

This question tests the developer's knowledge of these internals, which can be critical for writing efficient code.

6. How do you typically test your Go code? Have you used Go's built-in testing package or do you prefer external libraries?

Testing is a crucial part of maintaining code quality and reliability. This question helps determine whether the candidate is disciplined about testing, understands Go's built-in testing capabilities, and is able to make informed decisions about when to use external libraries.

7. Can you describe a project where you've made use of Go's standard library?

Go has a comprehensive standard library that is designed to be used for a broad array of common programming tasks.

A good Go developer should be familiar with it, as using the standard library often leads to more consistent and maintainable code.

8. How do you handle error handling in Go? Can you provide an example of a custom error type you've created?

Error handling is a vital aspect of Go, which doesn't have the traditional try/catch mechanism seen in many other languages.

This question will help assess the candidate's understanding of Go's unique approach to error handling and their ability to create custom error types.

9. How you would use a buffered vs. unbuffered channel in Go?

Channels in Go are a core concept, particularly for managing concurrency. Buffered and unbuffered channels behave differently, and an experienced Go developer should understand these differences and know when to use each one.

10. In what scenarios would you choose to use pointers in Go? Can you talk about a project where pointers were crucial?

Pointers can be a complex concept for new programmers, but they are vital for certain types of programming tasks.

This question will help you understand the developer's proficiency with this important concept and their ability to use it appropriately.

11. Discuss your experience with Go's package management. Have you worked with Go Modules?

Package management is a key part of most non-trivial development projects. Go Modules is the official dependency management solution in Go, so experience with this tool is a strong indication of the candidate's ability to work effectively on large Go projects.

12. Explain how the defer statement is used in Go, and why it's beneficial. Can you give a real-world example?

The defer keyword in Go allows programmers to schedule a function call to be run after the function completes. It's a key aspect of Go's approach to resource cleanup and error handling.

Understanding its use and importance is indicative of a candidate's knowledge of idiomatic Go.

13. Have you ever used Go’s first-class functions in a project?

Go supports first-class functions, which means functions can be assigned to variables, passed as arguments to other functions, and more. This allows for flexible and powerful programming patterns, so understanding it is a good sign of a strong Go developer.

14. How would you implement polymorphism in Go?

Go doesn't support traditional object-oriented programming, so it doesn't have classes and inheritance.

However, it is possible to achieve polymorphic behavior using interfaces. Understanding this concept shows the candidate's ability to implement complex design patterns in Go.

15. Explain the difference between the “make” and “new” functions in Go. When would you use each?

“Make” and “new” are both used for memory allocation in Go, but they're used in different ways. An experienced Go developer should understand the difference and when to use each. Their answer will reveal their understanding of Go's memory allocation.

Is there another way to assess Go skills?

While interview questions are undoubtedly valuable, they can sometimes be subjective or rely on the interviewer's interpretation.

To make the hiring process more data-driven, it is beneficial to complement the interview questions with a Go test.

Our Go test assesses a candidate's ability to apply their knowledge in real-world scenarios, showcasing their problem-solving skills, code structure, and adherence to best practices.

This combination of Go interview questions and Go programming skills tests provides a comprehensive evaluation of a candidate's coding abilities, ultimately leading to a more informed hiring decision.