Rack::Deflater is compressing already compressed content like png and jpg images (which is waste of time and resources). In other servers we can selectively compress the content, and I missed this on rack today. What do you guys think?
I usually place Rack::Deflater downstream of any static asset server for this reason.
If you need to compress static assets, I have an open PR #479 that changes Rack::File to serve precompressed gzipped assets from the filesystem, if present. If you think that would be useful, throw it a +1.
also see #457