I have started my current first real job 8 months ago. I have gotten experience working in a team on a project. I have gained experience in C# Asp.Net Core (.Net 5), SQL, Frontend Development, Nginx, Logging, Deployment, …

I have learned a lot but recently I feel like I have hit a plateau. I still gain experience but I don’t feel like I am really improving too much.
I wonder where to go from here. Should I dipe deeper into what I already know? How? Should I learn something completely different meanwhile? What?

You may hit a comfort zone where you feel like you can perform well, its easy to get stuck in this bubble. Its in the human nature.
To improve you need to keep working outside of this zone, maybe not all day long since its exhausting. But try some new technologies. Maybe expand knowledge of cloud services like Azure or try some NoSQL if you only worked with SQL.

You may try some frontend like React or Vue. But I prefer developers with deep knowledge in one tech than mediocre in 2 or 3.
Do some code katas and practise more complex algoritms.
Side projects have helped me learn the most over the years. I’d suggest finding a github project you’re interested in and start helping out. You could also create your own.

You never hit that in our world, you hit a comfort spot like I like to call them, try different methods of archiving the same things, play with language features and go down the strange world of optimizing server apps.
Or you can go with another project, graphics, algorithms, AI, you know, getting to know code better or something about you.Also improving is weird, slow,fast, that’s is subjective, important is not to stay in that comfort spot

Very correct. I study game Engineering and I found it really helpful to dive into a topic that always was “black magic” to me. That way you learn new concepts and aside from that you can put those side projects into your portfolio. My current side project is writing my own “virtual machine” starting from designing the instruction set, implementing my own cpu/memory bus and writing an Assembler from scratch. It’s just a matter of staying curious about unfamiliar topics.

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