- Use `ApiError` as the error type for API routes
- The return type of an HTTP route should not be `HttpResponse` if possible; always prefer more specific types
  - Use `web::Json<T>` for JSON-encoded response
  - Use `()` for no content
- Prefer `ApiError` variants:
  - `ApiError::Request` instead of `ApiError::InvalidInput`
  - `ApiError::Auth` instead of `ApiError::CustomAuthentication`
  - `ApiError::Internal` for database errors, 3rd party service errors, anything else internal
  - Use `eyre!` to construct a value for `Internal`, `Request`, and `Auth` variants
- Error messages (both for errors and exceptions) must be formatted as per the Rust API guidelines:
  - lowercase message
  - no trailing punctuation
  - wrap code items e.g. type names in backticks
- Prefer `wrap_internal_err`, `wrap_request_err` when attaching context to an existing error (like Anyhow `context` or Eyre `wrap_err`)
- Prefer importing `eyre::Result` and using `Result<T>` instead of `eyre::Result<T>`
- Prefer `eyre::Ok(value)` instead of `Ok::<_, eyre::Report>(value)` when an explicit Eyre result type is needed
- All operations should ideally have some context attached
  - Database operations can have a message like `.wrap_internal_err("fetching XYZ")`
- You can perform real-time queries against the databases in the Docker Compose
  - `docker exec labrinth-postgres psql -c "select 1"`
  - `docker exec labrinth-redis redis-cli flushall`
  - `docker exec labrinth-clickhouse clickhouse-client "select 1"`
  - On some machines, you may have to use `podman` instead of `docker` - check which one is available first
- Hardcoded credentials for admin:
  - `Authorization: Bearer mra_admin` for default admin user
  - `Authorization: Bearer mra_user` for a regular user
  - `Modrinth-Admin: feedbeef` as admin key
- If some steps require you to create a project/mod or version for testing, ask the user to go into the web frontend and manually create a project/version
- When using `sqlx::query` etc. always use the macro form like `sqlx::query!` or `sqlx::query_scalar!` - never the plain function form. Avoid using `query_as!`.
- Do not use `()` as an error type for operations, unless you have a very good reason. Either make a new error type, or use `eyre::Report`.
- Do not run `cargo test`, even for a single specific test, unless explicitly prompted to by the user, since it takes a long time to run.
- You can force a search reindex by:
  - Running `cd apps/labrinth && cargo run -p labrinth -- --run-background-task index-search` (prefer this if backend is running locally)
  - Hitting the force reindex admin endpoint
- To seed the database locally: `psql postgresql://labrinth:labrinth@localhost/labrinth -f apps/labrinth/fixtures/labrinth-seed-data-202508052143.sql`
- When writing `sqlx` queries, prefer `r#` raw strings over escaping quotes
- When interacting with the Postgres database, prefer using a `ro_pool: ReadOnlyPgPool` when performing read-only operations
- After writing a SQL query, run `EXPLAIN ANALYZE` to see how long the query would take to run. Report to the user the estimated performance impact of the query.