Best country for grinding a low-level programming career?
Turning 27 soon, reaching 5 years of experience this July, specializing in low-level software development, so OS and OS-adjacent projects, embedded systems, compilers, high-performance systems with low-level optimization work, anything made in C or a similar language, or that needs to be optimized to the last CPU cycle, I'd love working on.
Thing is, young and inexperienced me has made a number of mistakes career-wise, so anyone on here wiser and more experienced than me when it comes to that, giving me advise, I would highly appreciate it.
I graduated with a 1st class honors in my BSc Computer Science in London, got my 1st job in Cambridge but got sick of living in England and wanted to see how things on the tech market scene are like back at home in Bulgaria. Leaving that job was my first gargantuan career mistake - I was in the team that does the primary development of one of the leading hypervisors, basically any low-level systems developer's dream team to grow in. Young and inexperienced me wasn't realizing that. That job lasted a little under a year.
Going back to Bulgaria was my next gargantuan career mistake. The number of companies actually seeking advanced developers here and giving them a chance to grow into senior devs (rather than severely underpaid code monkeys) and work on the kind of projects I wanna work on, are counted on my fingers. Most are web or app development companies using Bulgaria as a low-cost center, nothing more and nothing less.
Despite that, I did have a job lined up before I decided to return to Bulgaria, as an OS developer, it was an in-house operating system almost nobody has heard of, but still low-level programming. Stayed there for nearly 3 years and left due to poor growth, usage of languages and tech the rest of the world has never even heard of and poor management. Had 2 short jobs after that, first one was over partly my fault partly company's fault, 2nd one they loved me but unfortunately client cancelled the project I was supposed to be getting placed in, so they had no choice but to let me go.
That was in December, been jobless ever since. I have been getting interviews at a steady pace, which is good news, but all have concluded in my rejection so far. I'm using this in-between jobs time now to get started with my first ever Free and Open Source software contribution, contributing to GCC. Started with an easyhack, looking to move to more substantial contributions later.
Question for you guys is - which country should I try to move to, if I just wanna grind at a job hard, see my career skyrocket and earn tons of money, for the foreseeable future, as a developer of operating systems / embedded systems / compilers / anything low-level and optimized?
I do have my UK work permit still too and obviously all of EU. I've heard Germany is quite
bad right now. What countries in Europe, as well as outside Europe, are available for me to easily go and get a job at? I'm open to go anywhere in the world, my circumstances allow for that. Where should my sight be turned to? Japan? China? Scandinavia? Switzerland? Cyprus? Back to the UK? I also have a US visa but for some reason it only allows me to go there, not get a job there. Is there a way to get that upgraded?
I just wanna grind like crazy for career growth for the next few years, basically. Bulgaria is far from a place where I can do that, as a low-level systems developer, it seems. Thanks to everyone in advance for any career advise.