---
description: Idiomatic Go style (Effective Go + Code Review Comments)
globs: ["**/*.go"]
alwaysApply: true
---

- Format with `gofmt`; tabs for indentation, no parentheses on `if`/`for`/`switch`.
- `MixedCaps`/`mixedCaps`, never underscores. Capitalized first letter = exported.
- Package names: short, lower-case, single word. No `util`/`common`/`misc`; don't stutter.
- Getters drop `Get` (`Owner()`/`SetOwner()`). One-method interfaces use the `-er` suffix.
- Initialisms keep consistent case: `ServeHTTP`, `appID`, `URL`.
- Error strings lower-case, no trailing punctuation; prefix with the operation/package.
- Handle every error — return, handle, or panic. Never discard with `_`. Don't `panic` for normal flow.
- Avoid in-band errors; return an extra `error` or `ok bool`.
- Check errors early and return; keep the happy path at minimal indentation; drop the `else` after a terminating `if`.
- Keep interfaces small. Accept interfaces, return concrete types. Define them in the consuming package, not "for mocking".
- "Do not communicate by sharing memory; instead, share memory by communicating" — prefer channels and `select`.
- Pass `context.Context` as the first parameter; prefer synchronous functions.
- Receiver names: consistent 1–2 letter abbreviation of the type, never `me`/`this`/`self`.
- Pointer receiver to mutate / large structs / `sync.Mutex`; value receiver for small immutable types; when in doubt, pointer.
- `defer` cleanup after acquiring the resource. `new(T)` for zeroed `*T`, `make` for slices/maps/channels.
- Doc comments: full sentences starting with the name, ending with a period.
- Use `crypto/rand` for keys/secrets, never `math/rand`.