Gábor, Ludo',

Gábor Boskovits 写道：
> Supressing the last modified header is just an
> add_header Last-Modified "";
> away.

You'll also need:

# Don't honour client If-Modified-Since constraints.
if_modified_since off;
# Nginx's etags are hashes of file timestamp & file length.
etag off;

Turning these off will of course prevent all caching.  I don't 
know if that would add measurable load to guix.gnu.org (it would 
be more problematic if we used a CDN, but it might still make a 
difference).

Nix does something both interesting and icky — as always: patch[0] 
nginx to look up the realpath() instead, so clients can still 
cache using If-None-Match.

Kind regards,

T G-R

[0]: https://github.com/NixOS/nixpkgs/pull/48337