Golang

See: Golang Cheatsheet

Benefits

• Statically typed — fewer runtime bugs
• Fast builds, fast feedback loop
• Small binaries and containers — quick deploys, low memory usage
• Simple, explicit code; minimal magic
• Strong standard library — particularly for networking and HTTP

Shortcomings

• Go is still not good
• Go programs are not portable
• Lies we tell ourselves to keep using Golang

Concurrency

• Goroutines, channels, select
• sync.Mutex, sync.RWMutex, sync.WaitGroup
• Buffered vs unbuffered channels
• Production concurrency
• Context — context.WithTimeout, context.WithCancel, context.WithoutCancel

HTTP / API Frameworks

• The standard library covers most needs (net/http, http.ServeMux)
• chi — net/http-compatible router, idiomatic, well maintained
• Echo — fuller framework if needed

JSON

• Use json.Unmarshal for one object, json.Decoder for a stream

Logging

• Use structured logging (slog in stdlib) to reduce allocations
• Add contextual fields (request ID, user, operation)

Testing

• testify — assertions
  • assert continues on failure
  • require stops the test on failure
• httpexpect — API tests
• Run with -race to catch data races

Gotchas

• A map only grows, it never shrinks — recreate if memory matters (100 Go mistakes)
• range produces a copy
• Avoid init()
• Slowloris / RUDY — set read and write timeouts on HTTP servers
• Define interfaces on the caller side, not the implementation side
• Slice gotchas
• Does Go have subtyping?

Compiling

• Statically linking Go
• Static Go
• cgo
• Consider goreleaser for release automation

Resources

• Tour of Go (beginner)
• Go by Example
• Effective Go
• Idiomatic Go
• 100 Go Mistakes
• The Zen of Go
• Which Go?
• Google Go style guide
• Best practices (2013)
• Less is exponentially more
• Faster Go code by being mindful of memory
• go embed