Actually, it looks like HttpBuildCacheCredentials might be more appropriate, but the docs still don’t mention which HTTP header it uses.

Ok, I did a simple hack, and I can see that gradle does use the HTTP

Authorization: Basic

header for its HttpBuildCacheCredentials. Where is the best place to file a documentation bug requesting this to be explicit? For starters, I filed an issue: https://github.com/gradle/gradle/issues/21833