feat(devShells): shell for NixOS configuration development

.envrc

@@ -1 +1,2 @@
 use flake .#nix
+use flake .#SkyOS

.gitignore

@@ -0,0 +1 @@
+.direnv/

devShells/default.nix

@@ -53,7 +53,8 @@ in
     }:
 
     {
-      devShells = builtins.listToAttrs (
+      devShells =
+        builtins.listToAttrs (
           map (name: {
             inherit name;
             value =
@@ -66,7 +67,18 @@ in
                 shellHook = cfg.shellHook or "";
               };
           }) dirs
-      );
+        )
+        // {
+          nixos =
+            let
+              cfg = import ./nixos.nix pkgs;
+            in
+            pkgs.mkShell {
+              name = "SkyOS";
+              packages = map (p: p) (builtins.attrValues cfg.packages);
+              shellHook = cfg.shellHook or "";
+            };
+        };
     };
   flake.templates = builtins.listToAttrs (
     map (name: {

devShells/nixos.nix

@@ -0,0 +1,25 @@
+# SkyOS
+/**
+  Development shell with tools needed for configuration editing
+*/
+pkgs: {
+  /**
+    tool for managing __runtime__ secrets. See [sops-nix](https://github.com/mic92/sops-nix) for more info
+  */
+  packages.sops = pkgs.sops;
+  /**
+    tool for managing __eval time__ secrets.
+
+    In near future, it's going to be replaced by my own project which uses `sops` instead of bare `age`
+  */
+  packages.git-agecrypt = pkgs.git-agecrypt;
+
+  /**
+    tool for generating documentation from comments in .nix files
+  */
+  packages.nixdoc = pkgs.nixdoc;
+  /**
+    tool for generating book from md files made by `nixdoc`
+  */
+  packages.mdbook = pkgs.mdbook;
+}