diff --git a/outputs/aarch64-darwin/default.nix b/outputs/aarch64-darwin/default.nix
index 7ff7b8ea..be8ddae7 100644
--- a/outputs/aarch64-darwin/default.nix
+++ b/outputs/aarch64-darwin/default.nix
@@ -19,3 +19,12 @@
   };
 in
   outputs
+  // {
+    inherit data; # for debugging purposes
+
+    # NixOS's unit tests.
+    evalTests = haumea.lib.loadEvalTests {
+      src = ./tests;
+      inputs = args // {inherit outputs;};
+    };
+  }
diff --git a/outputs/aarch64-darwin/tests/home-manager/expected.nix b/outputs/aarch64-darwin/tests/home-manager/expected.nix
new file mode 100644
index 00000000..50a9d707
--- /dev/null
+++ b/outputs/aarch64-darwin/tests/home-manager/expected.nix
@@ -0,0 +1,10 @@
+{
+  myvars,
+  lib,
+}: let
+  username = myvars.username;
+  hosts = [
+    "fern"
+  ];
+in
+  lib.genAttrs hosts (_: "/Users/${username}")
diff --git a/outputs/aarch64-darwin/tests/home-manager/expr.nix b/outputs/aarch64-darwin/tests/home-manager/expr.nix
new file mode 100644
index 00000000..0fa743ff
--- /dev/null
+++ b/outputs/aarch64-darwin/tests/home-manager/expr.nix
@@ -0,0 +1,15 @@
+{
+  myvars,
+  lib,
+  outputs,
+}: let
+  username = myvars.username;
+  hosts = [
+    "fern"
+  ];
+in
+  lib.genAttrs
+  hosts
+  (
+    name: outputs.darwinConfigurations.${name}.config.home-manager.users.${username}.home.homeDirectory
+  )
diff --git a/outputs/aarch64-darwin/tests/hostname/expected.nix b/outputs/aarch64-darwin/tests/hostname/expected.nix
new file mode 100644
index 00000000..83f0a9b9
--- /dev/null
+++ b/outputs/aarch64-darwin/tests/hostname/expected.nix
@@ -0,0 +1,8 @@
+{
+  lib,
+  outputs,
+}: let
+  hostsNames = builtins.attrNames outputs.darwinConfigurations;
+  expected = lib.genAttrs hostsNames (name: name);
+in
+  expected
diff --git a/outputs/aarch64-darwin/tests/hostname/expr.nix b/outputs/aarch64-darwin/tests/hostname/expr.nix
new file mode 100644
index 00000000..78f05d28
--- /dev/null
+++ b/outputs/aarch64-darwin/tests/hostname/expr.nix
@@ -0,0 +1,9 @@
+{
+  lib,
+  outputs,
+}:
+lib.genAttrs
+(builtins.attrNames outputs.darwinConfigurations)
+(
+  name: outputs.darwinConfigurations.${name}.config.networking.hostName
+)
diff --git a/outputs/default.nix b/outputs/default.nix
index a3f48513..70e7efbd 100644
--- a/outputs/default.nix
+++ b/outputs/default.nix
@@ -45,6 +45,7 @@
   allSystemNames = builtins.attrNames allSystems;
   nixosSystemValues = builtins.attrValues nixosSystems;
   darwinSystemValues = builtins.attrValues darwinSystems;
+  allSystemValues = nixosSystemValues ++ darwinSystemValues;
 
   # Helper function to generate a set of attributes for each system
   forAllSystems = func: (nixpkgs.lib.genAttrs allSystemNames func);
@@ -53,7 +54,7 @@ in {
   debugAttrs = {inherit nixosSystems darwinSystems allSystems allSystemNames;};
 
   # Unit Tests for all NixOS systems.
-  evalTests = lib.lists.all (it: it.evalTests == {}) nixosSystemValues;
+  evalTests = lib.lists.all (it: it.evalTests == {}) allSystemValues;
 
   # NixOS Hosts
   nixosConfigurations =
diff --git a/outputs/x86_64-darwin/default.nix b/outputs/x86_64-darwin/default.nix
index 7ff7b8ea..be8ddae7 100644
--- a/outputs/x86_64-darwin/default.nix
+++ b/outputs/x86_64-darwin/default.nix
@@ -19,3 +19,12 @@
   };
 in
   outputs
+  // {
+    inherit data; # for debugging purposes
+
+    # NixOS's unit tests.
+    evalTests = haumea.lib.loadEvalTests {
+      src = ./tests;
+      inputs = args // {inherit outputs;};
+    };
+  }
diff --git a/outputs/x86_64-darwin/tests/home-manager/expected.nix b/outputs/x86_64-darwin/tests/home-manager/expected.nix
new file mode 100644
index 00000000..f569ef0d
--- /dev/null
+++ b/outputs/x86_64-darwin/tests/home-manager/expected.nix
@@ -0,0 +1,10 @@
+{
+  myvars,
+  lib,
+}: let
+  username = myvars.username;
+  hosts = [
+    "harmonica"
+  ];
+in
+  lib.genAttrs hosts (_: "/Users/${username}")
diff --git a/outputs/x86_64-darwin/tests/home-manager/expr.nix b/outputs/x86_64-darwin/tests/home-manager/expr.nix
new file mode 100644
index 00000000..bfc15e8d
--- /dev/null
+++ b/outputs/x86_64-darwin/tests/home-manager/expr.nix
@@ -0,0 +1,15 @@
+{
+  myvars,
+  lib,
+  outputs,
+}: let
+  username = myvars.username;
+  hosts = [
+    "harmonica"
+  ];
+in
+  lib.genAttrs
+  hosts
+  (
+    name: outputs.darwinConfigurations.${name}.config.home-manager.users.${username}.home.homeDirectory
+  )
diff --git a/outputs/x86_64-darwin/tests/hostname/expected.nix b/outputs/x86_64-darwin/tests/hostname/expected.nix
new file mode 100644
index 00000000..83f0a9b9
--- /dev/null
+++ b/outputs/x86_64-darwin/tests/hostname/expected.nix
@@ -0,0 +1,8 @@
+{
+  lib,
+  outputs,
+}: let
+  hostsNames = builtins.attrNames outputs.darwinConfigurations;
+  expected = lib.genAttrs hostsNames (name: name);
+in
+  expected
diff --git a/outputs/x86_64-darwin/tests/hostname/expr.nix b/outputs/x86_64-darwin/tests/hostname/expr.nix
new file mode 100644
index 00000000..78f05d28
--- /dev/null
+++ b/outputs/x86_64-darwin/tests/hostname/expr.nix
@@ -0,0 +1,9 @@
+{
+  lib,
+  outputs,
+}:
+lib.genAttrs
+(builtins.attrNames outputs.darwinConfigurations)
+(
+  name: outputs.darwinConfigurations.${name}.config.networking.hostName
+)