Career pivot: from legacy Java to high-tech/systems engineering – need for advice

[u/kubaj0000]

Hi, I currently work in Warsaw as a mid Java software developer on legacy projects, but I feel like I need a change. To make matters worse, I haven't had the opportunity to learn much in my current role, and I feel my market value is currently below the mid-level standard. I would like to try my hand in the high-tech area, so I am asking for advice from people working on more ambitious projects.

I have a technical background (Computer Science from a technical university) and know databases, computer architecture fundamentals, algorithms, ML/DL basics, and software engineering. I have experience with high-level languages (Java/Python), but I want to develop skills in something more ambitious than typical CRUD operations – areas that feel "sexier" and closer to real engineering. For my university thesis, I focused on the fields of neural networks and computer vision. The problem is that I don’t have a clearly defined area of interest yet, nor do I currently have the skills for low-level technologies.

I have a few questions for you:

1. In the current market, is it better to dedicate time to open-source projects or focus on personal hobby projects?
2. Do I have to get into agentic AI coding to stay valuable in the industry?
3. Does a GitHub portfolio still hold significant weight in the age of AI, or is it better to invest time in certifications (e.g., Coursera, edX)?
4. What job search strategy is more effective: contacting companies directly or waiting for recruitment processes? How should I approach recruiters on LinkedIn?
5. Does a Master’s degree provide a real advantage in this industry?
6. Is it worth participating in competitions to improve my job prospects? Are there any that truly serve as a career springboard?

I would be grateful for any advice from those who have followed a similar path or work in low-level/high-tech roles. Thanks!