Golang Interview Questions

In an interview for a Go (Golang) developer position, you can expect questions that delve deep into the language's core features and idioms. Here are some key points and potential questions an interviewer might ask:

1. Concurrency

• Goroutines:
  • How do goroutines work in Go?
  • What happens if a goroutine panics? How can you handle it?
  • Can you explain how to manage goroutines to avoid memory leaks or excessive resource usage?
• Channels:
  • How do channels facilitate communication between goroutines? Can you provide an example?
  • What is the difference between buffered and unbuffered channels? When would you use each?
  • How would you implement a worker pool using goroutines and channels?
  • Explain the concept of channel direction and how it’s used in Go.
  • How do you handle channel closing, and what are the implications of closing a channel?

2. HTTP Operations

• HTTP Servers:
  • How do you set up an HTTP server in Go?
  • Can you describe how to handle different HTTP methods (GET, POST, PUT, DELETE) in Go?
  • How do you handle request context and cancellation in an HTTP server?
• HTTP Clients:
  • How do you perform HTTP requests in Go using the net/http package?
  • How would you handle timeouts and retries when making HTTP requests?
  • Can you explain how to manage cookies, headers, and authentication in HTTP requests?

3. Channels

• Channel Operations:
  • How do you use select with channels in Go? Can you provide an example?
  • What are common pitfalls when working with channels?
  • Explain how to use channels for synchronization between goroutines.
• Advanced Channel Usage:
  • How can you implement a publish-subscribe pattern using channels?
  • How do you implement a rate limiter using channels in Go?

4. Data Structures Usage

• Maps:
  • How do you work with maps in Go? What are their limitations?
  • How would you handle concurrent access to a map?
• Slices:
  • How do slices differ from arrays in Go?
  • Can you explain how slices are internally implemented and how that affects their usage?
  • What are some common slice operations, and how do you handle out-of-bounds errors?
• Structs:
  • How do you define and use structs in Go?
  • Can you explain the concept of embedding in Go structs and its use cases?

5. Interface Usage

• Basics:
  • What is an interface in Go, and how is it different from interfaces in other languages like Java or C#?
  • How do you implement and use interfaces in Go?
• Empty Interface:
  • What is the empty interface (interface{}) in Go, and how is it typically used?
  • How do you perform type assertions and type switches on an empty interface?
• Interface Design:
  • How do you design and use small, composable interfaces in Go?
  • Can you explain the concept of duck typing in Go with respect to interfaces?
  • What are the advantages and potential pitfalls of using interfaces in Go?

6. Memory Management

• Garbage Collection:
  • How does garbage collection work in Go?
  • What are some strategies to optimize memory usage in Go?
• Escape Analysis:
  • What is escape analysis, and how does it affect memory allocation in Go?

7. Error Handling

• Idiomatic Error Handling:
  • How is error handling typically done in Go?
  • What are the advantages and disadvantages of Go's error handling approach?
• Custom Error Types:
  • How do you create and use custom error types in Go?
  • How do you implement and handle error wrapping in Go 1.13+?

  ### 8. Go Idioms and Best Practices

• Testing:
  • How do you write and structure tests in Go?
  • What tools do you use for testing in Go (e.g., testing, testify)?
• Code Organization:
  • How do you structure a Go project?
  • What are the best practices for managing dependencies in Go (e.g., Go modules)?

9. Advanced Go Concepts

• Reflection:
  • What is reflection in Go, and how can it be used? What are the downsides?
• Panic and Recover:
  • How do you handle panics in Go, and when should you use recover?