nicer

$ nix build .#homeConfigurations.x86_64-linux.motiejusja.activationPackage
    warning: Git tree '/home/motiejus/code/config' is dirty
    error:
           … while calling the 'derivationStrict' builtin

             at /builtin/derivation.nix:9:12: (source not available)

           … while evaluating derivation 'home-manager-generation'
             whose name attribute is located at /nix/store/sb3x0gk95v9h285ch8cdqv3gfjp97p1b-source/pkgs/stdenv/generic/make-derivation.nix:348:7

           … while evaluating attribute 'buildCommand' of derivation 'home-manager-generation'

             at /nix/store/sb3x0gk95v9h285ch8cdqv3gfjp97p1b-source/pkgs/build-support/trivial-builders/default.nix:87:14:

               86|       enableParallelBuilding = true;
               87|       inherit buildCommand name;
                 |              ^
               88|       passAsFile = [ "buildCommand" ]

           (stack trace truncated; use '--show-trace' to show the full trace)

           error: A definition for option `home.packages' is not of type `list of package'. Definition values:
           - In `/nix/store/2mk1zyrkzf2cnhqhlvqr9wlbxfa4gymi-source/shared/home': <derivation nicer>

shared/home/default.nix

@@ -20,6 +20,31 @@
         go
         zig
       ])
+      (writeShellApplication {
+        name = "nicer";
+        text = ''
+          set -e
+          f=$(${coreutils}/bin/mktemp)
+          trap 'rm -f "$f"' EXIT
+          ${coreutils}/bin/env > "$f"
+          systemd-run \
+              --user \
+              --same-dir \
+              --slice nicer \
+              --nice=19 \
+              --property CPUSchedulingPolicy=idle \
+              --property IOSchedulingClass=idle \
+              --property IOSchedulingPriority=7 \
+              --pty \
+              --pipe \
+              --wait \
+              --collect \
+              --quiet \
+              --property EnvironmentFile="$f" \
+              --service-type=exec \
+              -- "$@"
+        '';
+      })
       (lib.mkIf hmOnly [
         pkgs.nixgl.nixGLIntel
         ncdu