From b6cad64ef6cbbfe48b920bfab51a41eeefe8b636 Mon Sep 17 00:00:00 2001
From: Sean Buckley <sean.bck@gmail.com>
Date: Thu, 27 Feb 2020 16:40:10 -0500
Subject: [PATCH 1/3] NixOS/auto-upgrade: Add optional randomized delay

---
 nixos/modules/tasks/auto-upgrade.nix | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/nixos/modules/tasks/auto-upgrade.nix b/nixos/modules/tasks/auto-upgrade.nix
index 7fe06699191..57ca7cd9419 100644
--- a/nixos/modules/tasks/auto-upgrade.nix
+++ b/nixos/modules/tasks/auto-upgrade.nix
@@ -63,6 +63,17 @@ let cfg = config.system.autoUpgrade; in
         '';
       };
 
+      randomizedDelaySec = mkOption {
+        default = "0";
+        type = types.str;
+        example = "45min";
+        description = ''
+          Add a randomized delay to wait before automatically upgrading.
+          The delay will be between zero and this value.
+          This value must be a valid systemd timestamp.
+        '';
+      };
+
     };
 
   };
@@ -109,6 +120,8 @@ let cfg = config.system.autoUpgrade; in
       startAt = cfg.dates;
     };
 
+    systemd.timers.nixos-upgrade.timerConfig.RandomizedDelaySec = cfg.randomizedDelaySec;
+
   };
 
 }

From 14a1aa4a3dbfbde733cbc133828cfca951e8bdf6 Mon Sep 17 00:00:00 2001
From: Sean Buckley <buckley310@users.noreply.github.com>
Date: Fri, 28 Feb 2020 12:03:41 -0500
Subject: [PATCH 2/3] NixOS/auto-upgrade: fix wording

Co-Authored-By: Pascal Hertleif <killercup@gmail.com>
---
 nixos/modules/tasks/auto-upgrade.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nixos/modules/tasks/auto-upgrade.nix b/nixos/modules/tasks/auto-upgrade.nix
index 57ca7cd9419..6eaa40613d1 100644
--- a/nixos/modules/tasks/auto-upgrade.nix
+++ b/nixos/modules/tasks/auto-upgrade.nix
@@ -70,7 +70,7 @@ let cfg = config.system.autoUpgrade; in
         description = ''
           Add a randomized delay to wait before automatically upgrading.
           The delay will be between zero and this value.
-          This value must be a valid systemd timestamp.
+          This value must be a valid systemd timespan.
         '';
       };
 

From 9d3aa711fe64868aa5a7ac5038a39b861cacefdb Mon Sep 17 00:00:00 2001
From: Sean Buckley <sean.bck@gmail.com>
Date: Tue, 3 Mar 2020 22:14:31 -0500
Subject: [PATCH 3/3] NixOS/auto-upgrade: refine option description

---
 nixos/modules/tasks/auto-upgrade.nix | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/nixos/modules/tasks/auto-upgrade.nix b/nixos/modules/tasks/auto-upgrade.nix
index 6eaa40613d1..bfc1e301efa 100644
--- a/nixos/modules/tasks/auto-upgrade.nix
+++ b/nixos/modules/tasks/auto-upgrade.nix
@@ -68,9 +68,11 @@ let cfg = config.system.autoUpgrade; in
         type = types.str;
         example = "45min";
         description = ''
-          Add a randomized delay to wait before automatically upgrading.
-          The delay will be between zero and this value.
-          This value must be a valid systemd timespan.
+          Add a randomized delay before each automatic upgrade.
+          The delay will be chozen between zero and this value.
+          This value must be a time span in the format specified by
+          <citerefentry><refentrytitle>systemd.time</refentrytitle>
+          <manvolnum>7</manvolnum></citerefentry>
         '';
       };