I got the following error while trying to build the snowflake proxy using go version 1.15 and that is currently mentioned as minimum requirement in the README.md
hnapel@raspberrypi:~/snowflake/proxy $ go build
../../firstname.lastname@example.org/curve25519/curve25519_go120.go:9:8: package crypto/ecdh is not in GOROOT (/usr/lib/go-1.15/src/crypto/ecdh)
This is solved by (manually) installing go version 1.20 (in my case using go1.20.6.linux-arm64.tar.gz) , also downloaded a new tree directly from:
git clone https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowflake.git
This is not currently reflected in the guide, which still points to the earlier git location.