Nginx host files created by a different service

Help
1

a service starts a program that creates static files that I want to host with nginx, but the service (specifally minecraft-server) creates these files not as the nginx user. And so nginx can’t access these files.

my idea was to just add nginx to a group with the minecraft user:

  users.groups.minecraft = {
    members = [
      config.users.users.minecraft.name
      config.services.nginx.user
    ];
  };

  systemd.services.minecraft-server = {
    serviceConfig = {
      Group = config.users.groups.minecraft.name;
    };
  };

but nginx still gives me a 403. just to test I also ran

chown minecraft:minecraft /var/lib/minecraft/ -R
chmod 2755 -R /var/lib/minecraft/plugins/dynmap/ -R

but still nginx can’t access these files.

What’s the recommended way to go about this?