simple direnv suppport, fix #199

Author: nim65s

nix/modules/default.nix

@@ -9,6 +9,7 @@
   imports = [
     ./environment.nix
     ./etc.nix
+    ./direnv.nix
     ./systemd.nix
     ./tmpfiles.nix
     ./upstream/nixpkgs

nix/modules/direnv.nix

@@ -0,0 +1,35 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.programs.direnv;
+in
+{
+  options.programs.direnv = {
+    enable = lib.mkEnableOption "direnv integration";
+    package = lib.mkPackageOption pkgs "direnv" { };
+    nix-direnv = {
+      enable = lib.mkEnableOption "nix-direnv integration";
+      package = lib.mkPackageOption pkgs "nix-direnv" { };
+    };
+  };
+  config = lib.mkIf cfg.enable {
+    environment = {
+      etc = {
+        "profile.d/direnv.sh".source = pkgs.writeText "direnv.sh" ''
+          eval "$(${lib.getExe cfg.package} hook bash)"
+        '';
+      };
+      systemPackages =
+        [
+          cfg.package
+        ]
+        ++ lib.optionals cfg.nix-direnv.enable [
+          cfg.nix-direnv.package
+        ];
+    };
+  };
+}