Hi! Ludovic Courtès skribis: > This is because with ‘filtered-port’, the input port is dumped from a > child process, not from the calling process. I decided to take a heavy-handed solution to that problem, which is to augment Guile-zlib with an interface for gzip compression/decompression not restricted to file ports (‘call-with-gzip-output-port’ & co. are restricted to file ports): https://notabug.org/guile-zlib/guile-zlib/commit/b899ac2fecf91475da1eba7e7b24708ea8b5fb73 That way, we can change ‘decompressed-port’ in (guix utils) to perform in-process decompression for ‘gzip’, like it does for zstd and lzip. If everything goes well, I’ll cut a Guile-zlib release today and update Guix accordingly. Ludo’.