Auth0 - Auth0 is a program for people to get authentication and authorization services for their own business use.
MySQL - The world's most popular open source database
Spring Security - The Spring portfolio has many projects, including Spring Framework, Spring IO Platform, Spring Cloud, Spring Boot, Spring Data, Spring Security...
PostgreSQL - PostgreSQL is a powerful, open source object-relational database system.
Firebase Authentication - Application and Data, Application Utilities, and User Management and Authentication
SQLite - SQLite Home Page