I'm in the insanely lucky position to be making a GBA game for a living right now... But before getting to this point, I had some day jobs, and worked on the game on weekends.
First I sold my soul to work in mobile games (well, at what was initially a small & very creative studio) in the Netherlands, which is where I met Rik and we started making Goodboy in our spare time. As time went on, the nature of projects we were working on at the day job got worse, and we both grew tired of being milked for our creativity to make shallow ad machines.
But yeah, the trick to making progress on Goodboy during that time was to arrange to meet up with Rik every other weekend. I could never have done it by myself, but when you set aside time to jam it out with another person, you can really keep up the momentum that way.
After a couple of years I handed in my notice and moved back to the UK for a job in web development, just as the pandemic struck. Unlike the last job, this one was for a good cause. But it was infuriating in its own way because the processes were sluggish, the team was underqualified, and the technology stack was atrocious. PHP + Jira + being stuck in Teams meetings for hours every day is a really brain-rotting combo!
The stuff I did for the GBA community during that time (helping to set up GBA Jam 2021 and such) was basically done while procrastinating from work to keep myself sane. But this also had its toll, because my resulting focus & productivity issues (undiagnosed ADHD maybe?) meant I was basically "at my job" for every waking hour, as I'd feel obliged to catch up on all the work I didn't do during the day.
The silver lining was that I was able to negotiate Fridays off, which I dedicated to working on the game. If you ever have this opportunity and can afford to, freaking take it!
We kept plugging away at the game on Fridays & weekends for another year and a half, and eventually were able to get everything into gear for the Kickstarter campaign. And it took off, because we had the right headlines at the right time (20th anniversary of the GBA, first commercial GBA game in 13 years (yes, that's a stretch, we really meant something more specific than that)), and a physical publisher who could push the story through their own channels, and we reached out to retro gaming YouTubers, and spread it on Twitter as far as we could. But on top of all that, we had a great trailer and great demo to back it up.
So that's the story of how I tanked 4 years of psychic damage to break free and go full time indie, with a lot of luck too. But it's not over, we still have to finish the full game... And do the Switch port. And we have no idea how successful the final thing will be, we can only hope it's enough to sustain us so we can keep doing this!