diff --git a/dev/flake-module.nix b/dev/flake-module.nix
index ae227e5..95dcb4a 100644
--- a/dev/flake-module.nix
+++ b/dev/flake-module.nix
@@ -30,5 +30,10 @@
     # for repl exploration / debug
     config.config = config;
     options.mySystem = lib.mkOption { default = config.allSystems.${builtins.currentSystem}; };
+    config.effects = withSystem "x86_64-linux" ({ config, pkgs, hci-effects, ... }: {
+      tests = {
+        template = pkgs.callPackage ./tests/template.nix { inherit hci-effects; };
+      };
+    });
   };
 }
diff --git a/dev/tests/template.nix b/dev/tests/template.nix
new file mode 100644
index 0000000..04671fa
--- /dev/null
+++ b/dev/tests/template.nix
@@ -0,0 +1,37 @@
+{ hci-effects, nix, git, path }:
+
+hci-effects.mkEffect {
+  inputs = [ nix git ];
+  effectScript = ''
+    ann() { # announce
+      printf '\n\e[34;1m%s\e[0m\n' "$*"
+    }
+    mkdir -p ~/.config/nix
+    echo 'experimental-features = nix-command flakes' >>~/.config/nix/nix.conf
+    mkdir clean
+    cd clean
+
+    ann nix flake init...
+    nix -v flake init -t ${../..}
+
+    ann pointing to local sources...
+    sed -i flake.nix -e 's^nixpkgs.url = ".*";^nixpkgs.url = "${path}"; flake-parts.url = "${../..}";^'
+    # head flake.nix
+    grep -F ${path} flake.nix >/dev/null
+
+    ann nix flake lock...
+    nix flake lock
+
+    ann nix flake show...
+    nix -v flake show
+
+    ann nix build...
+    nix build .
+
+    ann checking result...
+    readlink ./result | grep hello
+
+    echo
+    printf '\n\e[32;1m%s\e[0m\n' 'All good!'
+  '';
+}