Sequelize

Sequelize is an open source, promise-based ORM for Node.js and TypeScript. It works with several SQL databases and handles models, relations, transactions and migrations.

You define models in code, and Sequelize maps them to tables and builds the queries for you. Associations such as belongs-to and has-many let you load related records with simple methods. It supports transactions, eager and lazy loading, soft deletion and lifecycle hooks. It can also sync models to the database, which is handy for quick prototypes.

• Models and associations between tables
• Transactions for safe multi-step writes
• Soft deletion that keeps removed records
• Lifecycle hooks around queries
• Support for Oracle, Postgres, MySQL, SQLite and more

Node.js developers who want a well-documented ORM for web apps and APIs that use a relational database. Backend teams that need transactions and associations will find the feature set useful.

Sequelize is free and open source under the MIT license. Its docs cover version 6, and the upgrade guide helps with newer changes. Automatic sync is handy for prototypes, but use migrations for schema changes in production.