From fa8c65f3a25c68a289610ffc88d1e4df69240ecd Mon Sep 17 00:00:00 2001
From: Tom van Dijk <18gatenmaker6@gmail.com>
Date: Fri, 1 May 2026 11:49:25 +0200
Subject: [PATCH] feat: preferLocalBuild

The apps exported like `write-flake` are written in a way that nix will first
try to reach out to caches and remote builders before performing a local build.
This is very annoying since it slows down the build a lot, especially if you
have a lot of caches (nix-community.cachix.org, cache.garnix.io, etc.). But
caches and remote builders will never be able to serve these, so it is
pointless in even trying.

This patch adds preferLocalBuild to all `runCommand`'s and `mkDerivation`'s
I found with `rg`.
---
 modules/write-flake.nix  | 3 ++-
 modules/write-inputs.nix | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/modules/write-flake.nix b/modules/write-flake.nix
index 8501a2f..33dc05d 100644
--- a/modules/write-flake.nix
+++ b/modules/write-flake.nix
@@ -89,6 +89,7 @@ let
       name = "flake-formatted";
       passAsFile = [ "unformatted" ];
       inherit unformatted;
+      preferLocalBuild = true;
       phases = [ "format" ];
       format = ''
         cp $unformattedPath flake.nix
@@ -126,7 +127,7 @@ let
         (lib.concatStringsSep "\n")
       ];
     in
-    pkgs.runCommand "check-flake-file"
+    pkgs.runCommandLocal "check-flake-file"
       {
         nativeBuildInputs = [ pkgs.diffutils ];
       }
diff --git a/modules/write-inputs.nix b/modules/write-inputs.nix
index a658f98..8c26890 100644
--- a/modules/write-inputs.nix
+++ b/modules/write-inputs.nix
@@ -20,6 +20,7 @@ let
       copy = ''
         cp $inputsStringPath $out
       '';
+      preferLocalBuild = true;
     };
 
   write-inputs =