Startups will often take anyone who's willing to apply, and your full stack experience will come in handy too.
Another alternative is contracting. Those who hire contractors usually don't have the manpower to test extensively, and they're more likely to trust you to deliver. Or not care that much because you'll be working on a non-core element.
I am really invested in the things I do and put everything I have into them. I prefer to think like a product owner so contacting is out. While I’d have more autonomy, I’d have less say on the product and would find that unfulfilling.
I had the same idea about startups but have failed numerous technical interviews for positions I was probably overqualified for. Even asked a few for accommodations for my ASD/ADHD in testing but no go.
Depends on who you contract for. I've done contracts as "first engineer". Many are from rich people who own a factory and such but know nothing about apps. Some from people who are good at raising money, but not hiring; people who are qualified to be tech leads can be very picky.
Some have a loose idea of what they want but need someone to guide them on what is or isn't possible. There's room for mistakes, and some flexibility.
http://angel.co/ is a common one, although some of the startups are a bit sketch, so you gotta do your research. https://topstartups.io/ filters for higher-quality startups
Permatemp roles are more abundant and pay better. But the others are not that rare. I never had difficulty finding these roles; it's been more work turning away clients than marketing. YMMV.
Many are those are dead end projects that never get off the ground, or don't have enough budget for a marketing team and a full MVP. Many are part time founders who make good money and want to throw money at a side project, but aren't fully focused. There's a lot of downsides to the path too.
Another alternative is contracting. Those who hire contractors usually don't have the manpower to test extensively, and they're more likely to trust you to deliver. Or not care that much because you'll be working on a non-core element.