Email Template Freemarker Freemarker is one of my favorite template engine for emails It provides rich features to manage complex logics using parent-child template formatting Online FreeMarker Template Tester is really helpful and handy to test your templates IntelliJ Ultimate support developing freemarker templates out of the box Thymeleaf Thymeleaf is really handy for simple and lightweight email templates Thymeleaf and SpringMail is one of the best combination in my opinion IntelliJ Ultimate supports thymeleaf development out of the box Tip Mailpit is email & SMTP testing tool with API, it is really helpful for local development to run local SMTP server and visualise using builtin UI and can also be used inn unit and integration testing with builtin REST API. Implementation Reference: Journey-API