It is a #DebianPolicy violation for building packages to download arbitrary things from the network, so that will have to be disabled during package builds, at least...
#GoLang itself seems to have a decent history of #ReproducibleBuilds for versions 1.20 and 1.19, at least:
https://tests.reproducible-builds.org/debian/history/golang-1.20.html
https://tests.reproducible-builds.org/debian/history/golang-1.19.html
The one package off the top of my head built with golang, #nncp also seems to have a good history of building reproducibly:
https://tests.reproducible-builds.org/debian/history/nncp.html
#debianpolicy #goLang #reproduciblebuilds #NNCP