From 044318babcc425bc937723f623a609f6064a6b2a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Geoffrey=20=E2=80=9CFrogeye=E2=80=9D=20Preud=27homme?=
 <geoffrey@frogeye.fr>
Date: Mon, 1 Apr 2024 14:59:07 +0200
Subject: [PATCH] Display changed derivations on activation

---
 hm/nix/default.nix  |  1 +
 os/default.nix      |  1 +
 os/diff/default.nix | 14 ++++++++++++++
 3 files changed, 16 insertions(+)
 create mode 100644 os/diff/default.nix

diff --git a/hm/nix/default.nix b/hm/nix/default.nix
index deb58ac..e5b2f23 100644
--- a/hm/nix/default.nix
+++ b/hm/nix/default.nix
@@ -2,6 +2,7 @@
 {
   config = {
     home.packages = with pkgs; [
+      nvd
       nix-diff
       nix-tree
       nix-output-monitor
diff --git a/os/default.nix b/os/default.nix
index 786f1e0..dafd85f 100644
--- a/os/default.nix
+++ b/os/default.nix
@@ -8,6 +8,7 @@
     ./ccc
     ./common.nix
     ./desktop.nix
+    ./diff
     ./gaming
     ./geoffrey.nix
     ./printing
diff --git a/os/diff/default.nix b/os/diff/default.nix
new file mode 100644
index 0000000..ccd5611
--- /dev/null
+++ b/os/diff/default.nix
@@ -0,0 +1,14 @@
+{ pkgs, lib, config, ... }:
+{
+  config = {
+    system.activationScripts.diff = {
+      supportsDryActivation = true;
+      text = ''
+        if [ -h /run/current-system ]
+        then
+            ${pkgs.nvd}/bin/nvd --nix-bin-dir=${pkgs.nix}/bin diff /run/current-system "$systemConfig"
+        fi
+      '';
+    };
+  };
+}