Very cool, always love seeing adventures in codegen. If you want to see what something like this looks like after many years of development, after you discover all those day-2 issues in code gen at scale...

intro code gen docs: https://hofstadter.io/getting-started/code-generation/

core code gen package: https://github.com/hofstadter-io/hof/tree/_next/lib/gen

you'll likely want to move from printf to text/template and then put a schema on the input data, then put the templates as files on disk so you can iterate faster without needing to recompile the binary to adjust the code that comes out

btw, you contributed the built binary to your git repo