Bookshelf.js

Bookshelf is a Node.js ORM built on Knex query builder, supporting PostgreSQL, MySQL, and SQLite3. Version 1.2.0 (latest stable) is actively maintained with a test suite on Travis CI. It provides promise-based and callback interfaces, eager/nested-eager loading, transactions, and polymorphic associations. Unlike full-featured ORMs like Sequelize, Bookshelf is lean, data-mapper oriented, and encourages dropping to raw Knex for custom queries. Release cadence is irregular, with security fixes prioritized. Requires peer dependency knex >=0.15.0 <0.22.0 and a database driver (pg, mysql, sqlite3).