Go Safety

Quick Reference

Risk	Fix
Typed nil in interface	Return untyped `nil`, never a typed nil pointer
Nil map write	`make` or lazy-init in the method
`append` aliasing	Cap-limit before growing; clone for independent elements; both are shallow
Bare type assertion	Always comma-ok: `v, ok := x.(T)`
`defer` in loop	Extract body to a function
Integer narrowing	Bounds-check against `math.MaxInt32` first
Float comparison	choose domain-specific absolute/relative tolerances; handle NaN/infinity explicitly
Iota enum	Plain `iota` from 0 with a real state at zero (default); `iota + 1` only if zero-as-invalid genuinely matters
Mutable global	Inject `func() time.Time`
Crypto keys	`rand.Read()` + `hex.EncodeToString` (or `rand.Int(rand.Reader, ...)`); `rand.Text()` (Go 1.24+) is a shorthand alt