---
description: Go conventions and patterns for this project
globs: "**/*.go"
alwaysApply: false
---

# Go Conventions

## Context

Every exported function that does I/O takes `context.Context` as its first argument.

## Errors

- Define package-level sentinel errors for expected conditions:

```go
var ErrNotFound = fmt.Errorf("not found")
```

- Wrap unexpected errors with `fmt.Errorf("doing X: %w", err)` to preserve the chain.
- Callers check expected errors with `errors.Is(err, store.ErrNotFound)`.

## UUIDs

- Use `github.com/google/uuid` for all UUID types.
- Model structs use `uuid.UUID`, not `string`, for ID fields.

## Database

- Use `?` parameter placeholders (MySQL style), never string interpolation.
- Use `gen_random_uuid()` for server-generated UUIDs (Postgres built-in).
- **Queries**: use [sqlc](https://sqlc.dev/) to generate type-safe Go from SQL.
  Write annotated SQL in `internal/store/queries/*.sql`; run `task sqlc` to
  regenerate. Never hand-write query code in Go — edit the `.sql` source instead.

## Testing

- Use the standard `testing` package. No external assertion libraries.
- Test functions follow `TestTypeName_MethodName` naming