Cygnet is a PostgreSQL-only async Python ORM that embraces SQL rather than hiding it. Its API uses uppercase method names for SQL keywords and lowercase for Python utilities, making queries readable and predictable. Key design choices include: no base class or metaclass inheritance, a plain dataclass model, an AST-based query builder that emits parameterized SQL in one pass, and strict safety rails (UPDATE/DELETE require explicit WHERE, typo'd field names raise errors). It natively supports PostgreSQL-specific features like JSONB, LATERAL joins, CTEs, window functions, ON CONFLICT upserts, RETURNING, FOR UPDATE SKIP LOCKED, and server-side cursor streaming. The library is driver-agnostic at its core, with psycopg3 as an optional extra, and requires Python 3.12+ and PostgreSQL 14+.
