Databases
PostgreSQL
PostgreSQL is the most powerful open-source relational database — stable, reliable, and the mainstream pick for SaaS backends.
Beginner-friendly3/5MySQL
MySQL is the world's most widely used open-source relational database — mature, stable, resource-rich, an evergreen of web backends.
Beginner-friendly4/5SQLite
SQLite is an extremely lightweight embedded database — 'one file is one database', zero config and very easy to start.
Beginner-friendly5/5Cloudflare D1
D1 is 'SQLite running on the Cloudflare edge' — a big free tier and the best fit for SaaS starting at $0.
Beginner-friendly5/5MongoDB
MongoDB is the most popular NoSQL document database — flexible structure with no fixed schema, great for fast iteration.
Beginner-friendly3/5