By default, restic determines the location of the cache based on the XDG
base dir specification, which is `~/.cache/restic` when the environment
variable `$XDG_CACHE_HOME` isn't set.
As restic is executed as root by default, this resulted in the cache being
written to `/root/.cache/restic`, which is not quite right for a system
service and also meant, multiple backup services would use the same cache
directory - potentially causing issues with locking, data corruption,
etc.
The goal was to ensure, restic uses the correct cache location for a
system service - one cache per backup specification, using `/var/cache`
as the base directory for it.
systemd sets the environment variable `$CACHE_DIRECTORY` once
`CacheDirectory=` is defined, but restic doesn't change its behavior
based on the presence of this environment variable.
Instead, the specifier [1] `%C` can be used to point restic explicitly
towards the correct cache location using the `--cache-dir` argument.
Furthermore, the `CacheDirectoryMode=` was set to `0700`, as the default
of `0755` is far too open in this case, as the cache might contain
sensitive data.
[1] https://www.freedesktop.org/software/systemd/man/systemd.unit.html#Specifiers
The built-in default for unknown MIME-Types is `text/plain` whereas the
upstream default config changes it to `application/octet-stream`. By
changing the default tpye, unknown files will be downloaded by browsers
instead of being displayed.
The expression should check if the actually used nginx package
needes write+execute rights, not the default pkgs.nginx (which
has no modules unless overridden in an overlay).
Having MemoryDenyWriteExecute always true causes e.g. the Lua
module to fail (because JIT compilation).
Define systemd-socket activation using the upstream configuration
files as a reference. The "rsyncd" systemd unit has been renamed
to "rsync" for consistency with upstream.
OSS Emulation is considered incomplete so disabling it by default.
Using user level alsa-oss library (nix-env -iA nixos.alsaOss) over
this kernel module is recommended.