From 879c2dd588d42e6c09bec256a09d262c7abdce9d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sandro=20J=C3=A4ckel?= <sandro.jaeckel@gmail.com>
Date: Sat, 20 May 2023 02:24:32 +0200
Subject: [PATCH 1/2] nixos/nix-optimise: cleanup, remove with lib

---
 nixos/modules/services/misc/nix-optimise.nix | 34 +++++++-------------
 1 file changed, 11 insertions(+), 23 deletions(-)

diff --git a/nixos/modules/services/misc/nix-optimise.nix b/nixos/modules/services/misc/nix-optimise.nix
index db8148c060e7..58fc1ea4162a 100644
--- a/nixos/modules/services/misc/nix-optimise.nix
+++ b/nixos/modules/services/misc/nix-optimise.nix
@@ -1,28 +1,21 @@
 { config, lib, ... }:
 
-with lib;
-
 let
   cfg = config.nix.optimise;
 in
 
 {
-
-  ###### interface
-
   options = {
-
     nix.optimise = {
-
-      automatic = mkOption {
+      automatic = lib.mkOption {
         default = false;
-        type = types.bool;
+        type = lib.types.bool;
         description = lib.mdDoc "Automatically run the nix store optimiser at a specific time.";
       };
 
-      dates = mkOption {
+      dates = lib.mkOption {
         default = ["03:45"];
-        type = types.listOf types.str;
+        type = with lib.types; listOf str;
         description = lib.mdDoc ''
           Specification (in the format described by
           {manpage}`systemd.time(7)`) of the time at
@@ -32,9 +25,6 @@ in
     };
   };
 
-
-  ###### implementation
-
   config = {
     assertions = [
       {
@@ -43,14 +33,12 @@ in
       }
     ];
 
-    systemd.services.nix-optimise = lib.mkIf config.nix.enable
-      { description = "Nix Store Optimiser";
-        # No point this if the nix daemon (and thus the nix store) is outside
-        unitConfig.ConditionPathIsReadWrite = "/nix/var/nix/daemon-socket";
-        serviceConfig.ExecStart = "${config.nix.package}/bin/nix-store --optimise";
-        startAt = optionals cfg.automatic cfg.dates;
-      };
-
+    systemd.services.nix-optimise = lib.mkIf config.nix.enable {
+      description = "Nix Store Optimiser";
+      # No point this if the nix daemon (and thus the nix store) is outside
+      unitConfig.ConditionPathIsReadWrite = "/nix/var/nix/daemon-socket";
+      serviceConfig.ExecStart = "${config.nix.package}/bin/nix-store --optimise";
+      startAt = lib.optionals cfg.automatic cfg.dates;
+    };
   };
-
 }

From f2ea5c05c14e7c8ea962058f3028c2aca45993cd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sandro=20J=C3=A4ckel?= <sandro.jaeckel@gmail.com>
Date: Sat, 20 May 2023 02:32:19 +0200
Subject: [PATCH 2/2] nixos/nix-optimise: persist timer

otherwise the timer might never run on laptops which could be shutdown
during the night
---
 nixos/modules/services/misc/nix-optimise.nix | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/nixos/modules/services/misc/nix-optimise.nix b/nixos/modules/services/misc/nix-optimise.nix
index 58fc1ea4162a..0398229a13da 100644
--- a/nixos/modules/services/misc/nix-optimise.nix
+++ b/nixos/modules/services/misc/nix-optimise.nix
@@ -33,12 +33,19 @@ in
       }
     ];
 
-    systemd.services.nix-optimise = lib.mkIf config.nix.enable {
-      description = "Nix Store Optimiser";
-      # No point this if the nix daemon (and thus the nix store) is outside
-      unitConfig.ConditionPathIsReadWrite = "/nix/var/nix/daemon-socket";
-      serviceConfig.ExecStart = "${config.nix.package}/bin/nix-store --optimise";
-      startAt = lib.optionals cfg.automatic cfg.dates;
+    systemd = lib.mkIf config.nix.enable {
+      services.nix-optimise = {
+        description = "Nix Store Optimiser";
+        # No point this if the nix daemon (and thus the nix store) is outside
+        unitConfig.ConditionPathIsReadWrite = "/nix/var/nix/daemon-socket";
+        serviceConfig.ExecStart = "${config.nix.package}/bin/nix-store --optimise";
+        startAt = lib.optionals cfg.automatic cfg.dates;
+      };
+
+      timers.nix-optimise.timerConfig = {
+        Persistent = true;
+        RandomizedDelaySec = 1800;
+      };
     };
   };
 }