He's most likely saying that while the MAS is broken, you can still download something via git and build it yourself.
I'll just go compile my own PhotoShop, hang on.
No reason to downvote someone explaining it, seriously. You can downvote the original poster, if you want, but this just hurts everyone – he/she just wanted to help you out by explaining it.
You can compile the gimp.
I think the parent comment was suggesting to git-clone or wget and untar source, make and install.
So, instead of buying overpriced software from the mac store, just building it from source.