diff --git a/flake.nix b/flake.nix
index 1a6efe02..13c54cfc 100644
--- a/flake.nix
+++ b/flake.nix
@@ -79,9 +79,11 @@
       mapAttrs (_: project: mapAttrs (_: example: example.path) project.nixos.examples) rawNgiProjects
     );
 
-    rawNixosModules = flattenAttrsDot (lib.foldl recursiveUpdate {} (attrValues (
-      mapAttrs (_: project: project.nixos.modules) rawNgiProjects
-    )));
+    rawNixosModules = flattenAttrsDot (
+      lib.foldl recursiveUpdate {} (attrValues (
+        mapAttrs (_: project: project.nixos.modules) rawNgiProjects
+      ))
+    );
 
     nixosModules =
       {
@@ -175,8 +177,30 @@
           .options;
       };
     in rec {
+      # This is omitted in `nix flake show`.
       legacyPackages = {
-        nixosTests = mapAttrs (_: project: project.nixos.tests) ngiProjects;
+        # Run interactive tests with:
+        #
+        #     nix run .#legacyPackages.x86_64-linux.nixosTests.<project>.<test>.driverInteractive
+        #
+        nixosTests = let
+          nixosTest = test: let
+            # Amenities for interactive tests
+            tools = {pkgs, ...}: {
+              environment.systemPackages = with pkgs; [vim tmux jq];
+              # Use kmscon <https://www.freedesktop.org/wiki/Software/kmscon/>
+              # to provide a slightly nicer console.
+              # kmscon allows zooming with [Ctrl] + [+] and [Ctrl] + [-]
+              services.kmscon = {
+                enable = true;
+                autologinUser = "root";
+              };
+            };
+            debugging.interactive.nodes = mapAttrs (_: _: tools) test.nodes;
+          in
+            pkgs.nixosTest (debugging // test);
+        in
+          mapAttrs (_: project: mapAttrs (_: nixosTest) project.nixos.tests) ngiProjects;
       };
 
       packages =
@@ -205,7 +229,7 @@
       checks = let
         checksForNixosTests = projectName: tests:
           concatMapAttrs
-          (testName: test: {"projects/${projectName}/nixos/tests/${testName}" = test;})
+          (testName: test: {"projects/${projectName}/nixos/tests/${testName}" = pkgs.nixosTest test;})
           tests;
 
         checksForNixosExamples = projectName: examples:
diff --git a/projects/default.nix b/projects/default.nix
index 408e54e3..bb6b0e61 100644
--- a/projects/default.nix
+++ b/projects/default.nix
@@ -28,27 +28,11 @@
   in
     concatMapAttrs names (readDir baseDirectory);
 
-  nixosTest = test: let
-    # Amenities for interactive tests
-    tools = {pkgs, ...}: {
-      environment.systemPackages = with pkgs; [vim tmux jq];
-      # Use kmscon <https://www.freedesktop.org/wiki/Software/kmscon/>
-      # to provide a slightly nicer console.
-      # kmscon allows zooming with [Ctrl] + [+] and [Ctrl] + [-]
-      services.kmscon = {
-        enable = true;
-        autologinUser = "root";
-      };
-    };
-    debugging.interactive.nodes = mapAttrs (_: _: tools) test.nodes;
-  in
-    pkgs.nixosTest (debugging // test);
-
   hydrate = project: {
     packages = project.packages or {};
     nixos.modules = project.nixos.modules or {};
     nixos.examples = project.nixos.examples or {};
-    nixos.tests = mapAttrs (_: nixosTest) project.nixos.tests or {};
+    nixos.tests = project.nixos.tests or {};
   };
 in
   mapAttrs