The deciding difference is operational: Kubernetes can run on infrastructure you control, Fly.io cannot. If that constraint is real for you, it settles the choice before anything else is considered.
Long-running containers close to users, without owning a Kubernetes cluster.
Your existing cluster. Nothing new for the platform team to approve.
| Fly.io | Kubernetes | |
|---|---|---|
| Licence | Proprietary | Open source |
| Pricing | usage based | open source |
| Self-hostable | No | Yes |
| Languages | Any language | Any language |
| Install | brew install flyctl | — |
| Keys required | None | None |
The deciding difference is operational: Kubernetes can run on infrastructure you control, Fly.io cannot. If that constraint is real for you, it settles the choice before anything else is considered. Fly.io: Long-running containers close to users, without owning a Kubernetes cluster. Kubernetes: Your existing cluster. Nothing new for the platform team to approve.
Fly.io is a hosted service only. Kubernetes can run on your own infrastructure.
Fly.io is proprietary (usage based). Kubernetes is open source (open source).
Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.
curl -s -H "Accept: text/markdown" https://newagent.build/compare/fly-vs-k8s