Users of the knotserver module not using `nixos-unstable` faces the error linked below when rebuilding their system. Removing the usage of overlays, and instead using the existing `self.packages` functionality allow packages to be less dependent on the user's configuration, avoids a pitfall like this and is thus more reproducible. This patch also fixes the appview module referencing a non-existent package. This patch also removes redundant usages of `with final;` and includes some minor formatting done by alejandra. Minimum example: https://akyuu.soopy.moe/dGNHld.nix Example build failure with master branch tip: https://akyuu.soopy.moe/4aNh8c.txt