Why not Caqti?

Caqti is the mature choice, and the right one for MariaDB or Lwt. The rowtype library does less, Postgres and SQLite on Eio only, and in return gives you:

• a driver written for Eio, postgres-eio, rather than libpq bindings or a driver adapted to it;
• every statement checked against your database, from a test, without running it;
• migrations in the box, the same files and command for every dialect.