I’ve been having hard-to-debug caching issues serving up static files with nginx. It turns out this is due to nginx computing e-tag headers from file timestamps, which are all epoch in the guix store.
I’ve fixed this on my server by applying a patch from Nix: https://github.com/robx/guix/commit/4b406f5bc608b3c0e18e15795d8fe61d3477a3e2
