nzoschke/rack-streaming-proxy — comment on commit fef0d36b67e55644c627bca7da2e0cb01dfaa705
File:  line 0
By nzoschke:

It did in my case.

My client and backend are properly configured for chunked encoding, but the proxy was dropping the header.

I had to look very closely at the headers the proxy was getting, then setting for the request to the backend to figure this out.