Server-Sent Events (SSE) is a mechanism that can be used as an alternative to WebSockets to push streaming data to a client, there are many fundamental differences and a quick google search for “SSE vs WebSockets” will give you a lot of details if you want to understand both technologies
Reactive programming can be very exciting and fun to learn but it also can be challenging if you are used to more imperative programming.
R2DBC is a specification that provides database connectivity in a non blocking way and Spring Data R2DBC is one of the implementations of this specification. Reactive Connectivity for Relational Databases is still relatively new and, if like me, you are working with Kotlin it can be a little bit challenging
When I worked on my first Backend project, I realized how useful it was to have a process that allows you to track and manage changes in the Database and to be able to do it in a way that was easy to apply or rollback these changes to your different environments.