support for patching nixpkgs instance used by home manager

- introduce support for patching the used nixpkgs instance via
  `applyPatches`, see https://ertt.ca/nix/patch-nixpkgs/
- use patched nixpkgs instance in mkHomeManagern (TODO: use it in more
  places)
- add patch for nodejs-20 test failure in darwin (currently just in
  staging)

flake.lock

@@ -102,11 +102,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1746171682,
-        "narHash": "sha256-EyXUNSa+H+YvGVuQJP1nZskXAowxKYp79RNUsNdQTj4=",
+        "lastModified": 1747020534,
+        "narHash": "sha256-D/6rkiC6w2p+4SwRiVKrWIeYzun8FBg7NlMKMwQMxO0=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "50eee705bbdbac942074a8c120e8194185633675",
+        "rev": "b4bbdc6fde16fc2051fcde232f6e288cd22007ca",
         "type": "github"
       },
       "original": {
@@ -179,11 +179,11 @@
     },
     "nixos-hardware": {
       "locked": {
-        "lastModified": 1746621361,
-        "narHash": "sha256-T9vOxEqI1j1RYugV0b9dgy0AreiZ9yBDKZJYyclF0og=",
+        "lastModified": 1747129300,
+        "narHash": "sha256-L3clA5YGeYCF47ghsI7Tcex+DnaaN/BbQ4dR2wzoiKg=",
         "owner": "NixOS",
         "repo": "nixos-hardware",
-        "rev": "2ea3ad8a1f26a76f8a8e23fc4f7757c46ef30ee5",
+        "rev": "e81fd167b33121269149c57806599045fd33eeed",
         "type": "github"
       },
       "original": {
@@ -195,11 +195,11 @@
     },
     "nixos-unstable": {
       "locked": {
-        "lastModified": 1746461020,
-        "narHash": "sha256-7+pG1I9jvxNlmln4YgnlW4o+w0TZX24k688mibiFDUE=",
+        "lastModified": 1746904237,
+        "narHash": "sha256-3e+AVBczosP5dCLQmMoMEogM57gmZ2qrVSrmq9aResQ=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "3730d8a308f94996a9ba7c7138ede69c1b9ac4ae",
+        "rev": "d89fc19e405cb2d55ce7cc114356846a0ee5e956",
         "type": "github"
       },
       "original": {
@@ -243,11 +243,11 @@
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1746557022,
-        "narHash": "sha256-QkNoyEf6TbaTW5UZYX0OkwIJ/ZMeKSSoOMnSDPQuol0=",
+        "lastModified": 1746957726,
+        "narHash": "sha256-k9ut1LSfHCr0AW82ttEQzXVCqmyWVA5+SHJkS5ID/Jo=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "1d3aeb5a193b9ff13f63f4d9cc169fb88129f860",
+        "rev": "a39ed32a651fdee6842ec930761e31d1f242cb94",
         "type": "github"
       },
       "original": {
@@ -259,11 +259,11 @@
     },
     "nixpkgs_3": {
       "locked": {
-        "lastModified": 1746461020,
-        "narHash": "sha256-7+pG1I9jvxNlmln4YgnlW4o+w0TZX24k688mibiFDUE=",
+        "lastModified": 1746904237,
+        "narHash": "sha256-3e+AVBczosP5dCLQmMoMEogM57gmZ2qrVSrmq9aResQ=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "3730d8a308f94996a9ba7c7138ede69c1b9ac4ae",
+        "rev": "d89fc19e405cb2d55ce7cc114356846a0ee5e956",
         "type": "github"
       },
       "original": {
@@ -280,11 +280,11 @@
         "treefmt-nix": "treefmt-nix"
       },
       "locked": {
-        "lastModified": 1746740791,
-        "narHash": "sha256-4o0Aj9BXpybfAkcxY3h9+y0AuC5TtIVztuTdVXYubrI=",
+        "lastModified": 1747261242,
+        "narHash": "sha256-6p8kO62jbk+LUrDrLT23XbClNRyosnlfh/KCbE5fwnQ=",
         "owner": "nix-community",
         "repo": "NUR",
-        "rev": "228d29ab7ffa3f89d0088917883b179c7bce05f2",
+        "rev": "e29c558fa4174da179e2e7f9a41c34466a200fda",
         "type": "github"
       },
       "original": {

flake.nix

@@ -46,6 +46,16 @@
     let
       # FIXME: allow different systems
       systems = utils.lib.system;
+
+      # ability to extend nixpkgs with patches, e.g. from PRs or staging. See https://ertt.ca/nix/patch-nixpkgs/
+      mkNixpkgs-patched =
+        system:
+        (import nixpkgs { inherit system; }).applyPatches {
+          name = "nixpkgs-patched";
+          src = nixpkgs;
+          patches = [ ./patches/nixos-nixpkgs-362c2bc76d359b908ad1389ee28c23ee0e862324.patch ];
+        };
+
       # necessary to make the top-level inputs available to system configuration
       # inspired by https://jade.fyi/blog/flakes-arent-real/
       inputInjection =
@@ -78,7 +88,7 @@
       mkHomeManager =
         confName: user: system: # unfortunately, home-manager configs are still system-specific
         home-manager.lib.homeManagerConfiguration {
-          pkgs = nixpkgs.legacyPackages.${system};
+          pkgs = import (mkNixpkgs-patched system) { inherit system; };
           modules = [
             {
               imports = [

home/common.nix

@@ -73,6 +73,7 @@
         ''
       );
       core.whitespace = "-blank-at-eol,blank-at-eof,space-before-tab";
+      rerere.enabled = true;
     };
     lfs.enable = true;
     delta = {

patches/nixos-nixpkgs-362c2bc76d359b908ad1389ee28c23ee0e862324.patch

@@ -0,0 +1,26 @@
+From 362c2bc76d359b908ad1389ee28c23ee0e862324 Mon Sep 17 00:00:00 2001
+From: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>
+Date: Mon, 7 Apr 2025 21:03:09 -0400
+Subject: [PATCH] nodejs_20: fix test failure on darwin on latest MacOS 15.4
+
+Signed-off-by: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>
+(cherry picked from commit 9674c1f688d12b99fbde26e6068ab62609fef3b1)
+---
+ pkgs/development/web/nodejs/v20.nix | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/pkgs/development/web/nodejs/v20.nix b/pkgs/development/web/nodejs/v20.nix
+index b9c9345c441afa..20cceb5b5d1cda 100644
+--- a/pkgs/development/web/nodejs/v20.nix
++++ b/pkgs/development/web/nodejs/v20.nix
+@@ -50,5 +50,10 @@ buildNodejs {
+       stripLen = 1;
+       hash = "sha256-6y3aEqxNC4iTQEv1oewodJrhOHxjp5xZMq1P1QL94Rg=";
+     })
++    # fix test failure on macos 15.4
++    (fetchpatch2 {
++      url = "https://github.com/nodejs/node/commit/33f6e1ea296cd20366ab94e666b03899a081af94.patch?full_index=1";
++      hash = "sha256-aVBMcQlhQeviUQpMIfC988jjDB2BgYzlMYsq+w16mzU=";
++    })
+   ] ++ gypPatches;
+ }