Deploying a Spring Boot backend should be simple in theory. Build the JAR, set the environment variables, connect the database, and ship it. In practice, my deployment exposed several assumptions that worked locally but failed immediately in the cloud.
Source: [Dev.to](https://dev.to/ojo_ilesanmi/deploying-a-multi-module-spring-boot-app-to-render-with-postgresql-redis-docker-and-flyway-4leb)