c0f70b4694bb2be1c25ef0e23e3f11f9d718d162 removed the fixed uid
assignment, but then it becomes necessary to set isSystemUser.
http://hydra.nixos.org/build/22182588
These services don't create files on disk, let alone on a network
filesystem, so they don't really need a fixed uid. And this also gets
rid of a warning coming from <= 14.12 systems.
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
[Bjørn Forsman <bjorn.forsman@gmail.com>:
- use types.lines instead of types.string. The former joins strings
with "\n" and the latter with "" (and is deprecated).
]
