It's not the same. Guix also has "guix build --check" which builds a package a second time to compare potentially different results. "guix challenge" challeng

It's not the same. Guix also has "guix build --check" which builds a package a second time to compare potentially different results. "guix challenge" challenges different substitute servers and also compares what they offer with what you may have installed (whether you built it locally or downloaded it from elsewhere). It's really quite different from "guix build --check".