diff --git a/pkgs/by-name/ba/backlight-auto/package.nix b/pkgs/by-name/ba/backlight-auto/package.nix
deleted file mode 100644
index e6f849bf7096..000000000000
--- a/pkgs/by-name/ba/backlight-auto/package.nix
+++ /dev/null
@@ -1,37 +0,0 @@
-{
-  lib,
-  stdenv,
-  zig,
-  libyuv,
-  fetchFromGitHub,
-}:
-stdenv.mkDerivation (finalAttrs: {
-  pname = "backlight-auto";
-  version = "0.0.1";
-
-  src = fetchFromGitHub {
-    owner = "lf94";
-    repo = "backlight-auto";
-    rev = finalAttrs.version;
-    hash = "sha256-QPymwlDrgKM/SXDzJdmfzWLSLU2D7egif1OIUE+SHoI=";
-  };
-
-  nativeBuildInputs = [
-    zig.hook
-  ];
-
-  buildInputs = [
-    libyuv
-  ];
-
-  meta = with lib; {
-    # Does not support zig 0.12 or newer, hasn't been updated in 2 years.
-    broken = lib.versionAtLeast zig.version "0.12";
-    description = "Automatically set screen brightness with a webcam";
-    mainProgram = "backlight-auto";
-    homepage = "https://len.falken.directory/backlight-auto.html";
-    license = licenses.mit;
-    maintainers = [ ];
-    platforms = platforms.linux;
-  };
-})
diff --git a/pkgs/by-name/fa/fancy-cat/package.nix b/pkgs/by-name/fa/fancy-cat/package.nix
index f97cbbcb8284..641b50a7d707 100644
--- a/pkgs/by-name/fa/fancy-cat/package.nix
+++ b/pkgs/by-name/fa/fancy-cat/package.nix
@@ -12,7 +12,7 @@
   mupdf,
   openjpeg,
   stdenv,
-  zig,
+  zig_0_14,
 }:
 stdenv.mkDerivation (finalAttrs: {
   pname = "fancy-cat";
@@ -28,7 +28,7 @@ stdenv.mkDerivation (finalAttrs: {
   patches = [ ./0001-changes.patch ];
 
   nativeBuildInputs = [
-    zig.hook
+    zig_0_14.hook
   ];
 
   zigBuildFlags = [ "--release=fast" ];
@@ -56,6 +56,6 @@ stdenv.mkDerivation (finalAttrs: {
     license = lib.licenses.agpl3Plus;
     maintainers = with lib.maintainers; [ ciflire ];
     mainProgram = "fancy-cat";
-    inherit (zig.meta) platforms;
+    inherit (zig_0_14.meta) platforms;
   };
 })
diff --git a/pkgs/by-name/nc/ncdu/package.nix b/pkgs/by-name/nc/ncdu/package.nix
index 630dca3a9331..850f03521303 100644
--- a/pkgs/by-name/nc/ncdu/package.nix
+++ b/pkgs/by-name/nc/ncdu/package.nix
@@ -4,7 +4,7 @@
   fetchurl,
   ncurses,
   pkg-config,
-  zig_0_14,
+  zig_0_15,
   zstd,
   installShellFiles,
   versionCheckHook,
@@ -21,7 +21,7 @@ stdenv.mkDerivation (finalAttrs: {
   };
 
   nativeBuildInputs = [
-    zig_0_14.hook
+    zig_0_15.hook
     installShellFiles
     pkg-config
   ];
@@ -54,7 +54,7 @@ stdenv.mkDerivation (finalAttrs: {
       defelo
       ryan4yin
     ];
-    inherit (zig_0_14.meta) platforms;
+    inherit (zig_0_15.meta) platforms;
     mainProgram = "ncdu";
   };
 })
diff --git a/pkgs/by-name/ri/river-bedload/package.nix b/pkgs/by-name/ri/river-bedload/package.nix
index b0ac4f71acfe..71e4f8bd52d5 100644
--- a/pkgs/by-name/ri/river-bedload/package.nix
+++ b/pkgs/by-name/ri/river-bedload/package.nix
@@ -10,7 +10,7 @@
   wayland,
   wayland-protocols,
   wayland-scanner,
-  zig,
+  zig_0_14,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -28,7 +28,7 @@ stdenv.mkDerivation (finalAttrs: {
 
   nativeBuildInputs = [
     pkg-config
-    zig.hook
+    zig_0_14.hook
   ];
 
   buildInputs = [
diff --git a/pkgs/development/compilers/zig/generic.nix b/pkgs/development/compilers/zig/generic.nix
index 8d6af23eae29..b68750a56154 100644
--- a/pkgs/development/compilers/zig/generic.nix
+++ b/pkgs/development/compilers/zig/generic.nix
@@ -145,5 +145,9 @@ stdenv.mkDerivation (finalAttrs: {
     teams = [ lib.teams.zig ];
     mainProgram = "zig";
     platforms = lib.platforms.unix;
+    # Zig 0.15.1 fails some tests on x86_64-darwin thus we mark it broken
+    # see https://github.com/ziglang/zig/issues/24974
+    broken =
+      stdenv.hostPlatform.system == "x86_64-darwin" && lib.versionAtLeast finalAttrs.version "0.15";
   };
 })
diff --git a/pkgs/top-level/aliases.nix b/pkgs/top-level/aliases.nix
index 57c8b5c2fd42..5fb8852dd0eb 100644
--- a/pkgs/top-level/aliases.nix
+++ b/pkgs/top-level/aliases.nix
@@ -496,6 +496,7 @@ mapAliases {
 
   ### B ###
 
+  backlight-auto = throw "'backlight-auto' has been removed as it relies on Zig 0.12 which has been dropped."; # Added 2025-08-22
   badtouch = authoscope; # Project was renamed, added 20210626
   badwolf = throw "'badwolf' has been removed due to being unmaintained"; # Added 2025-04-15
   baget = throw "'baget' has been removed due to being unmaintained";
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 0cb1a9489e1b..33c29b27283a 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -9197,7 +9197,7 @@ with pkgs;
     zig_0_15
     ;
 
-  zig = zig_0_14;
+  zig = zig_0_15;
 
   zigStdenv = if stdenv.cc.isZig then stdenv else lowPrio zig.passthru.stdenv;