In another thread: Showroom work in progress - #2 by jan we discussed self-hosting with Microsoft IIS server.
We continued the discussion by email and it turned out that IIS is difficult to configure to serve already compressed resources with Content-Encoding: gzip header, because it compresses such resources the second time and browser can’t handle the result.
In such case the resources in a bundle can be uncompressed, so IIS handles the compression. For reference here is a shell script that can be used to decompresses resources in a bundle: Decompresses all compressed files in a Shapespark bundle · GitHub