Go Interview Questions: Basic to Advanced

1What is go build vs go run vs go install, and what problem does it solve?Basicconceptual30 minIn writing
2Walk me through how gopath vs go modules actually works under the hood.Basicconceptual35 minIn writing
3What's the practical difference that trips people up about go.mod and go.sum?Basicconceptual30 minIn writing
4How would you use cross-compilation with goos/goarch in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
5What's the tradeoff with gofmt and vet as forced style, and when would you choose differently?Intermediatepractical35 minIn writing
6What's a subtle bug or edge case people hit with when go is the wrong choice?Intermediateconceptual30 minIn writing
7In production, an issue traces back to go build vs go run vs go install. How do you diagnose and fix it?Scenarioscenario45 minIn writing
8Quiz: check your grasp of why go and the toolchain.Basicconceptual20 minIn writing

9What is Zero values by type, and what problem does it solve?Basicconceptual30 minIn writing
10Walk me through how var vs := short declaration actually works under the hood.Basicconceptual35 minIn writing
11What's the practical difference that trips people up about type conversion vs assertion?Basicconceptual30 minIn writing
12How would you use constants and iota in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
13What's the tradeoff with named types vs type aliases, and when would you choose differently?Intermediatepractical35 minIn writing
14What's a subtle bug or edge case people hit with integer overflow and sizing?Intermediateconceptual30 minIn writing
15In production, an issue traces back to zero values by type. How do you diagnose and fix it?Scenarioscenario45 minIn writing
16Quiz: check your grasp of types, variables, and zero values.Basicconceptual20 minIn writing

17What is Struct literals and embedding, and what problem does it solve?Basicconceptual30 minIn writing
18Walk me through how value receivers vs pointer receivers actually works under the hood.Basicconceptual35 minIn writing
19What's the practical difference that trips people up about method sets?Basicconceptual30 minIn writing
20How would you use composition over inheritance in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
21What's the tradeoff with anonymous structs, and when would you choose differently?Intermediatepractical35 minIn writing
22What's a subtle bug or edge case people hit with struct tags and reflection basics?Intermediateconceptual30 minIn writing
23In production, an issue traces back to struct literals and embedding. How do you diagnose and fix it?Scenarioscenario45 minIn writing
24Quiz: check your grasp of structs, methods, and composition.Basicconceptual20 minIn writing

25What is Implicit interface satisfaction, and what problem does it solve?Basicconceptual30 minIn writing
26Walk me through how empty interface and any actually works under the hood.Basicconceptual35 minIn writing
27What's the practical difference that trips people up about type assertions vs type switches?Basicconceptual30 minIn writing
28How would you use interface segregation in go in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
29What's the tradeoff with nil interfaces vs nil concrete values, and when would you choose differently?Intermediatepractical35 minIn writing
30What's a subtle bug or edge case people hit with accept interfaces, return structs?Intermediateconceptual30 minIn writing
31In production, an issue traces back to implicit interface satisfaction. How do you diagnose and fix it?Scenarioscenario45 minIn writing
32Quiz: check your grasp of interfaces and type assertions.Basicconceptual20 minIn writing

33What is Value semantics vs pointer semantics, and what problem does it solve?Basicconceptual30 minIn writing
34Walk me through how when to use a pointer receiver actually works under the hood.Basicconceptual35 minIn writing
35What's the practical difference that trips people up about escape analysis basics?Basicconceptual30 minIn writing
36How would you use passing large structs efficiently in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
37What's the tradeoff with pointer arithmetic's absence, and when would you choose differently?Intermediatepractical35 minIn writing
38What's a subtle bug or edge case people hit with new() vs make()?Intermediateconceptual30 minIn writing
39In production, an issue traces back to value semantics vs pointer semantics. How do you diagnose and fix it?Scenarioscenario45 minIn writing
40Quiz: check your grasp of pointers and value vs reference semantics.Basicconceptual20 minIn writing

41What is Arrays vs slices, and what problem does it solve?Basicconceptual30 minIn writing
42Walk me through how slice header: pointer, length, capacity actually works under the hood.Basicconceptual35 minIn writing
43What's the practical difference that trips people up about append() and reallocation?Basicconceptual30 minIn writing
44How would you use slicing shares memory in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
45What's the tradeoff with map iteration order and zero values, and when would you choose differently?Intermediatepractical35 minIn writing
46What's a subtle bug or edge case people hit with nil maps vs empty maps?Intermediateconceptual30 minIn writing
47In production, an issue traces back to arrays vs slices. How do you diagnose and fix it?Scenarioscenario45 minIn writing
48Quiz: check your grasp of slices, arrays, and maps.Basicconceptual20 minIn writing

49What is error as a return value, and what problem does it solve?Basicconceptual30 minIn writing
50Walk me through how sentinel errors vs errors.is/as actually works under the hood.Basicconceptual35 minIn writing
51What's the practical difference that trips people up about wrapping errors with %w?Basicconceptual30 minIn writing
52How would you use custom error types in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
53What's the tradeoff with when not to ignore an error, and when would you choose differently?Intermediatepractical35 minIn writing
54What's a subtle bug or edge case people hit with errors vs panics?Intermediateconceptual30 minIn writing
55In production, an issue traces back to error as a return value. How do you diagnose and fix it?Scenarioscenario45 minIn writing
56Quiz: check your grasp of error handling idioms.Basicconceptual20 minIn writing

57What is defer execution order (LIFO), and what problem does it solve?Basicconceptual30 minIn writing
58Walk me through how panic and stack unwinding actually works under the hood.Basicconceptual35 minIn writing
59What's the practical difference that trips people up about recover inside a deferred function?Basicconceptual30 minIn writing
60How would you use cleanup patterns with defer in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
61What's the tradeoff with when panic is appropriate, and when would you choose differently?Intermediatepractical35 minIn writing
62What's a subtle bug or edge case people hit with re-panicking after logging?Intermediateconceptual30 minIn writing
63In production, an issue traces back to defer execution order (lifo). How do you diagnose and fix it?Scenarioscenario45 minIn writing
64Quiz: check your grasp of panic, recover, and defer.Basicconceptual20 minIn writing

65What is Goroutines vs OS threads, and what problem does it solve?Basicconceptual30 minIn writing
66Walk me through how gomaxprocs and the m:n scheduler actually works under the hood.Basicconceptual35 minIn writing
67What's the practical difference that trips people up about goroutine leaks?Basicconceptual30 minIn writing
68How would you use starting and stopping goroutines cleanly in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
69What's the tradeoff with stack growth for goroutines, and when would you choose differently?Intermediatepractical35 minIn writing
70What's a subtle bug or edge case people hit with cooperative scheduling points?Intermediateconceptual30 minIn writing
71In production, an issue traces back to goroutines vs os threads. How do you diagnose and fix it?Scenarioscenario45 minIn writing
72Quiz: check your grasp of goroutines and the go scheduler.Basicconceptual20 minIn writing

73What is Buffered vs unbuffered channels, and what problem does it solve?Basicconceptual30 minIn writing
74Walk me through how closing channels and the ok idiom actually works under the hood.Basicconceptual35 minIn writing
75What's the practical difference that trips people up about select with multiple cases?Basicconceptual30 minIn writing
76How would you use nil channel behavior in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
77What's the tradeoff with fan-in / fan-out patterns, and when would you choose differently?Intermediatepractical35 minIn writing
78What's a subtle bug or edge case people hit with deadlocks from unbuffered sends?Intermediateconceptual30 minIn writing
79In production, an issue traces back to buffered vs unbuffered channels. How do you diagnose and fix it?Scenarioscenario45 minIn writing
80Quiz: check your grasp of channels and select.Basicconceptual20 minIn writing

81What is sync.Mutex vs sync.RWMutex, and what problem does it solve?Basicconceptual30 minIn writing
82Walk me through how sync.waitgroup for fan-out completion actually works under the hood.Basicconceptual35 minIn writing
83What's the practical difference that trips people up about sync/atomic operations?Basicconceptual30 minIn writing
84How would you use sync.once for lazy init in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
85What's the tradeoff with when to prefer a mutex over a channel, and when would you choose differently?Intermediatepractical35 minIn writing
86What's a subtle bug or edge case people hit with copying a mutex by value?Intermediateconceptual30 minIn writing
87In production, an issue traces back to sync.mutex vs sync.rwmutex. How do you diagnose and fix it?Scenarioscenario45 minIn writing
88Quiz: check your grasp of sync primitives (mutex, waitgroup, atomic).Basicconceptual20 minIn writing

89What is Data races vs logical races, and what problem does it solve?Basicconceptual30 minIn writing
90Walk me through how go run -race and the race detector actually works under the hood.Basicconceptual35 minIn writing
91What's the practical difference that trips people up about worker pool pattern?Basicconceptual30 minIn writing
92How would you use pipeline pattern with channels in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
93What's the tradeoff with context-based cancellation across goroutines, and when would you choose differently?Intermediatepractical35 minIn writing
94What's a subtle bug or edge case people hit with common goroutine leak sources?Intermediateconceptual30 minIn writing
95In production, an issue traces back to data races vs logical races. How do you diagnose and fix it?Scenarioscenario45 minIn writing
96Quiz: check your grasp of concurrency patterns and race conditions.Basicconceptual20 minIn writing

97What is context.Context propagation, and what problem does it solve?Basicconceptual30 minIn writing
98Walk me through how withcancel, withtimeout, withdeadline actually works under the hood.Basicconceptual35 minIn writing
99What's the practical difference that trips people up about context.value and its limits?Basicconceptual30 minIn writing
100How would you use cancellation vs error handling in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
101What's the tradeoff with respecting ctx.done() in long loops, and when would you choose differently?Intermediatepractical35 minIn writing
102What's a subtle bug or edge case people hit with context leaks from missing cancel()?Intermediateconceptual30 minIn writing
103In production, an issue traces back to context.context propagation. How do you diagnose and fix it?Scenarioscenario45 minIn writing
104Quiz: check your grasp of context package and cancellation.Basicconceptual20 minIn writing

105What is Package visibility (exported vs unexported), and what problem does it solve?Basicconceptual30 minIn writing
106Walk me through how module versioning and semantic import paths actually works under the hood.Basicconceptual35 minIn writing
107What's the practical difference that trips people up about go mod tidy and vendor?Basicconceptual30 minIn writing
108How would you use internal packages in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
109What's the tradeoff with avoiding import cycles, and when would you choose differently?Intermediatepractical35 minIn writing
110What's a subtle bug or edge case people hit with replacing a dependency locally?Intermediateconceptual30 minIn writing
111In production, an issue traces back to package visibility (exported vs unexported). How do you diagnose and fix it?Scenarioscenario45 minIn writing
112Quiz: check your grasp of packages, modules, and dependency management.Basicconceptual20 minIn writing

113What is table-driven tests, and what problem does it solve?Basicconceptual30 minIn writing
114Walk me through how testing.b benchmarks actually works under the hood.Basicconceptual35 minIn writing
115What's the practical difference that trips people up about pprof for cpu and memory profiles?Basicconceptual30 minIn writing
116How would you use test doubles via interfaces in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
117What's the tradeoff with go test -cover, and when would you choose differently?Intermediatepractical35 minIn writing
118What's a subtle bug or edge case people hit with fuzzing with go test -fuzz?Intermediateconceptual30 minIn writing
119In production, an issue traces back to table-driven tests. How do you diagnose and fix it?Scenarioscenario45 minIn writing
120Quiz: check your grasp of testing, benchmarking, and profiling.Basicconceptual20 minIn writing

121What is Stack vs heap allocation, and what problem does it solve?Basicconceptual30 minIn writing
122Walk me through how escape analysis and go build -gcflags actually works under the hood.Basicconceptual35 minIn writing
123What's the practical difference that trips people up about gc pacing and gogc?Basicconceptual30 minIn writing
124How would you use reducing allocations in hot paths in a real implementation, and what would you watch out for?Intermediatepractical35 minIn writing
125What's the tradeoff with sync.pool for reuse, and when would you choose differently?Intermediatepractical35 minIn writing
126What's a subtle bug or edge case people hit with memory profiling a leak?Intermediateconceptual30 minIn writing
127In production, an issue traces back to stack vs heap allocation. How do you diagnose and fix it?Scenarioscenario45 minIn writing
128Quiz: check your grasp of memory management and garbage collection.Basicconceptual20 minIn writing