The closest thing i can think of is ngnix - if i remember correctly, cloudflare built their business on top of ngnix in early days

“Just” run ngnix on your own servers from different geo locations. ngnix is very versatile, eg, load balancing, rate limiting, rule based firewall, caching…

but one important reason why saas/api/cloud businesses exist is that people don’t want to run their own servers for every project.