Hi, inspired by the tiny image for the static Web server “goStatic” as shown in Serve Small With Fly.io and GoStatic, I have just published an equally tiny read-only TFTP server, also written in Go/Golang, and as a minimal example that uses UDP on Fly.io instead of TCP for a change.
While the README.md is still a bit “uncooked”, the example builds, deploys, and works. Just make sure that you force your TFTP client to connect over IPv4, in case it sits on a dual-stack network like mine, at least until Fly supports UDP over IPv6 as well 
Comments, suggestions, issues, and PRs are welcome. Thank you.