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. ⭐ Courses with real-life practices ⭐ Save countless hours of time ⭐ 100% money back guarantee for 30 days ⭐ Become a professional Android developer now: https://pl-coding.com/premium-courses/ Download IntelliJ: https://www.jetbrains.com/idea/download Mongo Atlas registration: https://www.mongodb.com/products/platform/atlas-database 💻 Let me be your mentor and become an industry-ready Android developer in 10 weeks: https://pl-coding.com/drop-table-mentoring/ Regular programming advice on my Instagram page: https://www.instagram.com/_philipplackner_/ Join my Discord server: https://discord.gg/cwQbmUstEu Get the source code for this video here: https://github.com/philipplackner/SpringBootCrashCourse Kotlin Crash Course: https://youtu.be/dzUc9vrsldM?si=8vGs792MWd4_cEyX 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 bugs