I believe Alpine is GPL licensed. Curious what companies are using Alpine? What ramifications does this have on the licensing of a micro service running in Alpine.
The GPL only comes into effect when you redistribute software. Since most companies will probably use it to deploy their own software, GPL does not matter much in practice.
Besides that, for an application only the licenses of libraries that you link against are relevant.
You can't use the GPL for an entire distribution. You could argue that it's possible to only package GPL-compatible software and sublicense all of it under the GPL. This is impractical because of MPL and LGPL libraries. But even then the distribution isn't under the GPL, so you could inject an "MIT version" of musl and other non-GPL versions of the rest of the software.
tl;dr: That's not how licenses work.
There have been some interesting questions about packaging Ubuntu and their terms of use. I always found their terms of use odd, because they are basically reinstating trademark law inside a software license.
