Get a job making 120-180 but 4 days a week. It is possible to do this. Make sure it is not an exciting company, but rather a corporate, slow moving one.
Now you can pick up a contract making 100+ per hour. 15-20 hours a week.
Do 4 hours of the main job. Do 4 hours of the freelance work.
You’ll easily be making 250k.
Another thing to note, as a developer you can solve a problem in 1 hour that may take others 4,5, or 10. At your full time job, schedule your work and spread out when you complete tasks.
I’ve found this is a solid way to make a lot of money 200-300k, at non FAANG, and I have been able to fit it all into 4 days every week. I also work less than 40 hours on average. I’m not affiliated with it, but there is a site called overemployed with more tips on doing this.
The key is getting a really slow, easy remote job first. This is easy to manage if you’re a good senior dev