We have all broken apps by fat fingering a config or clicking the wrong checkbox in a control panel for an important piece of infrastructure. And we've sweat profusely while deploying load balancer or caching service changes on live applications.
Tools built for server ops aren't typically much fun for developers. We want our source control and test suite and build system and continuous deployments.
Fly is built for developers, and we started with a familiar set of tools and workflow. Edge Applications are meant to be developed, tested, and managed locally. And deployed using a sane, repeatable pipeline.
Write code, run
Build + Deploy with your favorite CI tool
Infrastructure as a runtime
Fly started when we wondered "what would a programmable edge look like"? Developer workflows work great for infrastructure like CDNs and optimization services. You should really see for yourself, though.