Fxicfg is a starlark interpreter for generating textproto inputs to Fuchsia recipes. This tool is temporary, it should eventually be superceded by LUCI's lucicfg.
go install fuchsia.googlesource.com/infra/infra/cmd/fxicfg fxicfg help
To generate protos, be sure to run this in the same directory as main.star.
fxicfg generate main.star
By default, this writes files into a “generated” directory. Any files in generated that weren't generated by main.star are removed.
See the configuration files in fuchsia.git for example starlark.