add dev-shell

.devcontainer/devcontainer.json

@@ -9,13 +9,16 @@
 	},
 	"customizations": {
 		"vscode": {
+			"settings": {
+				"terminal.integrated.defaultProfile.linux": "dev-shell"
+			},
 			"extensions": [
 				"formulahendry.dotnet-test-explorer",
 				"jnoortheen.nix-ide",
 				"eamodio.gitlens"
 			]
 		}
-	},
+	}
 
 	// Features to add to the dev container. More info: https://containers.dev/features.
 	// "features": {},
@@ -29,7 +32,7 @@
 	// }
 
 	// Use 'postCreateCommand' to run commands after the container is created.
-	"postCreateCommand": "nix-env -i nixpkgs-fmt"
+	// "postCreateCommand": "nix-env -i nixpkgs-fmt"
 
 	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
 	// "remoteUser": "root"

.vscode/settings.json

@@ -1,3 +1,10 @@
 {
-    "dotnet-test-explorer.testProjectPath": "**/*Tests.csproj"
+    "dotnet-test-explorer.testProjectPath": "**/*Tests.csproj",
+    "terminal.integrated.profiles.linux": {
+        "dev-shell": {
+            "path": "bash",
+            "args": [ "-c", "nix --experimental-features \"nix-command flakes\" develop"],
+            "overrideName": true
+        }
+    }
 }

flake.nix

@@ -194,8 +194,7 @@
         '';
       });
 
-    in
+    in rec {
-    rec {
       packages = forAllSystems (system: {
         default = nixpkgsFor.${system}.buildDotnetModule {
           pname = name;