Top 100 Golang Interview Questions

This top 100 Golang interview questions to help you prepare for your next technical interview. These questions are categorized for beginners, intermediate, and advanced levels to cover all aspects of the Go programming language:

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Beginner-Level Questions

1. What is Golang, and why is it used?
2. Explain the main features of Golang.
3. What are the advantages of using Go over other languages like Python or Java?
4. How do you declare variables in Go?
5. What are the different ways to declare constants in Go?
6. Explain the concept of “packages” in Go.
7. How do you write a “Hello, World!” program in Go?
8. What is the difference between var and := in Go?
9. Explain the defer keyword in Go.
10. What are pointers in Go? How do you use them?
11. What are the basic data types in Go?
12. How does error handling work in Go?
13. Explain the use of the fmt package in Go.
14. How do you create and use slices in Go?
15. What is a Go routine?
16. What are channels in Go, and why are they used?
17. How do you write a for loop in Go?
18. What is the difference between arrays and slices in Go?
19. How do you perform type casting in Go?
20. What is the iota keyword in Go?

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Intermediate-Level Questions

21. Explain the concept of interfaces in Go.
22. How do you implement polymorphism in Go?
23. What is the select statement in Go?
24. How does garbage collection work in Go?
25. What are the default values of variables in Go?
26. What are the built-in functions in Go?
27. Explain the difference between map and struct.
28. How do you handle JSON data in Go?
29. What is the purpose of the sync package in Go?
30. How do you perform unit testing in Go?
31. Explain the use of context in Go.
32. What is the reflect package used for?
33. How do you optimize Go programs for performance?
34. Explain the difference between buffered and unbuffered channels.
35. What are Go modules, and how do you use them?
36. How do you create a custom error type in Go?
37. Explain the panic and recover mechanisms in Go.
38. What is the difference between Runes and Bytes in Go?
39. How do you implement concurrency in Go?
40. How do you write a web server in Go?

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Advanced-Level Questions

41. What is a race condition? How do you prevent it in Go?
42. How does Go manage memory allocation?
43. Explain the internals of Go’s scheduler.
44. What are work-stealing algorithms in Go?
45. How do you profile a Go application?
46. How is dependency injection implemented in Go?
47. What is the purpose of the net/http package?
48. How do you handle file I/O in Go?
49. Explain the use of the time package in Go.
50. What are the differences between sync.Mutex and sync.RWMutex?
51. How do you handle signaling in Go?
52. What are embedded structs in Go?
53. Explain the difference between shallow copy and deep copy in Go.
54. What are variadic functions in Go?
55. How do you ensure thread safety in Go?
56. What is the Go toolchain, and how does it work?
57. How do you work with databases in Go?
58. What is the purpose of unsafe in Go?
59. How do you handle dependencies in a Go project?
60. Explain the design philosophy of Go.

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Scenario-Based Questions

61. How do you debug a deadlocked application in Go?
62. How would you implement a worker pool in Go?
63. How do you handle a long-running operation in a web server written in Go?
64. How do you implement a pub-sub system in Go?
65. How do you manage multiple modules in a Go project?
66. How do you optimize garbage collection in Go applications?
67. Explain how to implement retries with exponential backoff in Go.
68. How would you benchmark code in Go?
69. How do you secure a REST API written in Go?
70. How would you handle 1 million concurrent requests in Go?

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Practical Questions

71. Write a Go program to reverse a string.
72. How do you create a TCP server in Go?
73. Write a Go program to find the factorial of a number.
74. Write a Go program to implement a stack data structure.
75. How do you create a REST API in Go?
76. How do you parse command-line arguments in Go?
77. Write a Go program to sort an array.
78. How do you create and use a singleton pattern in Go?
79. How do you handle configuration management in Go?
80. Write a Go program to implement a simple cache.

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Behavioral Questions

81. What has been your most challenging Go project?
82. How do you stay updated with Go’s latest features?
83. Can you explain a situation where Go’s concurrency model helped solve a complex problem?
84. What are your best practices for structuring a Go project?
85. How do you approach debugging Go programs?

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Code Optimization Questions

86. How do you reduce memory usage in a Go application?
87. How do you prevent goroutine leaks?
88. What are some common pitfalls in Go programming?
89. How do you improve the performance of a Go web server?
90. How do you handle large files in Go?

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Specialized Questions

91. How do you write a microservice in Go?
92. What is the difference between Go and Rust?
93. How do you implement rate-limiting in Go?
94. How do you implement a circular buffer in Go?
95. What is a functional option pattern in Go?

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Future-Oriented Questions

96. What are some upcoming features in the latest Go versions?
97. How would you migrate an existing Go project to use Go modules?
98. What are the challenges of using Go in a distributed system?
99. How do you see the future of Golang in the software industry?
100. Why would you recommend Go for a project?

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These questions cover a range of topics from basic concepts to advanced scenarios, providing a comprehensive preparation guide for any Golang interview.