Merge pull request #36845 from jbedo/singularity

singularity: 2.4 -> 2.4.2

nixos/modules/module-list.nix

@@ -104,6 +104,7 @@
   ./programs/shadow.nix
   ./programs/shell.nix
   ./programs/spacefm.nix
+  ./programs/singularity.nix
   ./programs/ssh.nix
   ./programs/ssmtp.nix
   ./programs/sysdig.nix

nixos/modules/programs/singularity.nix

@@ -0,0 +1,20 @@
+{ config, pkgs, lib, ... }:
+
+with lib;
+let
+  cfg = config.programs.singularity;
+in {
+  options.programs.singularity = {
+    enable = mkEnableOption "Singularity";
+  };
+
+  config = mkIf cfg.enable {
+      environment.systemPackages = [ pkgs.singularity ];
+      systemd.tmpfiles.rules = [ "d /var/singularity/mnt/session 0770 root root -"
+                                 "d /var/singularity/mnt/final 0770 root root -"
+                                 "d /var/singularity/mnt/overlay 0770 root root -"
+                                 "d /var/singularity/mnt/container 0770 root root -"
+                                 "d /var/singularity/mnt/source 0770 root root -"];
+  };
+
+}