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Why babar?

See also: Get started, the Book.

babar is a Rust client for Postgres. There are several already. Why another one?

The short answer is one obvious way to do each thing. Connect, run a typed query, run a command, stream a result, manage a transaction, hold a pool, ingest with COPY, run migrations — there is one shape per task, and the codecs are values you import by name. The next time you read your own code, you can read it.

Three pillars

Ergonomic by design

Read it once, understand it forever. Queries are typed values. Codecs are imported by name. There is one way to start a transaction, one way to bind a parameter, one way to run a migration. You will not spend an afternoon learning which of seven options to use.

Postgres at heart

The wire protocol, faithfully. babar speaks Postgres directly — extended-protocol prepares, binary results, SCRAM-SHA-256, channel binding over TLS, and binary COPY FROM STDIN for bulk ingest. There is no translation layer between you and the server.

Built for the herd

Predictable under load. A single background task owns the socket and serializes wire I/O, so every public call is cancellation-safe. Pool, statement cache, and tracing spans are first-class — not bolted on later.

What “typed query” actually means

In babar, a Query<Params, Row> is a runtime value. It carries:

  • The SQL text.
  • A parameter encoder (Encoder<Params>).
  • A row decoder (Decoder<Row>).

When the type system says Query<(i32,), (Uuid, String, i64)>, the compiler knows the parameter shape, the row shape, and which codecs participate. There is no magic — Query::raw constructs one explicitly, and the query! macro builds the same thing with optional compile-time SQL verification.

What babar deliberately does not do

  • It does not require a compile-time database. query! against BABAR_DATABASE_URL is opt-in; the default Query::raw path runs without any dev-loop infrastructure.
  • It does not hide errors behind &dyn Error. babar::Error is a plain enum with eleven variants, each carrying the fields you need to decide what to do.
  • Design principles — typed, async, native protocol, validate-early, no-unsafe.
  • The driver task — the per-connection background task that makes every call cancellation-safe.
  • Comparisons — a trade-off-focused comparison table for tokio-postgres, sqlx, and diesel.
  • Roadmap — what’s in, what’s deferred, and where the project is going.