Full 2025 Backend Dev Crash Course for Beginners With Spring Boot (Kotlin, JWT Auth, MongoDB)

Get an introduction to building a CRUD backend that allows users to register and login and then save notes in a MongoDB instance. This crash course uses Kotlin and covers REST APIs from the absolute basics up to building a fully working secured backend.

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Kotlin Crash Course:    • Full 2025 Kotlin Crash Course For Beginners  

00:00 Prerequisites
1:43 - What even is a REST API?
7:25 - What is a backend framework?
9:55 - What we will build
11:02 - Creating a Spring Boot project
15:20 - Project roundtrip
21:18 - Mongo Atlas setup
33:14 - Saving notes to MongoDB
1:06:00 - Base setup for security config
1:12:55 - Checking notes in Mongo Atlas
1:14:24 - Spring's Bean mechanism
1:17:30 - Deleting notes
1:21:05 - Setting up the user collection
1:30:12 - JWT generation & verification
1:57:27 - User registration & login
2:35:55 - Responding with correct status codes
2:44:57 - Field validation
2:52:47 - Trying it out & fixing last bug