From 2d60dacd903608c2991481a094ea4509d58739a4 Mon Sep 17 00:00:00 2001
From: Guy Chronister <guychronister@outlook.com>
Date: Mon, 16 Feb 2026 13:45:31 -0600
Subject: [PATCH 1/2] mcfm: migrate to by-name, fix cmake version

---
 .../mc/MCFM/package.nix}                       | 18 ++++++++++++++----
 pkgs/top-level/all-packages.nix                |  8 --------
 2 files changed, 14 insertions(+), 12 deletions(-)
 rename pkgs/{applications/science/physics/MCFM/default.nix => by-name/mc/MCFM/package.nix} (68%)

diff --git a/pkgs/applications/science/physics/MCFM/default.nix b/pkgs/by-name/mc/MCFM/package.nix
similarity index 68%
rename from pkgs/applications/science/physics/MCFM/default.nix
rename to pkgs/by-name/mc/MCFM/package.nix
index 98b028c4da75..4ed8058f37d2 100644
--- a/pkgs/applications/science/physics/MCFM/default.nix
+++ b/pkgs/by-name/mc/MCFM/package.nix
@@ -1,12 +1,18 @@
 {
   lib,
-  stdenv,
   fetchurl,
   cmake,
   gfortran,
+  gccStdenv,
   lhapdf,
 }:
-
+let
+  stdenv = gccStdenv;
+  lhapdf' = lhapdf.override {
+    stdenv = gccStdenv;
+    python3 = null;
+  };
+in
 stdenv.mkDerivation rec {
   pname = "MCFM";
   version = "10.0.1";
@@ -18,15 +24,19 @@ stdenv.mkDerivation rec {
 
   postPatch = ''
     substituteInPlace CMakeLists.txt \
-      --replace 'target_link_libraries(mcfm lhapdf_lib)' \
+      --replace-fail 'target_link_libraries(mcfm lhapdf_lib)' \
                 'target_link_libraries(mcfm ''${lhapdf_lib})'
+
+    substituteInPlace qcdloop-2.0.5/CMakeLists.txt \
+    --replace-fail 'cmake_minimum_required (VERSION 3.0.2)' \
+    'cmake_minimum_required (VERSION 3.15)'
   '';
 
   nativeBuildInputs = [
     cmake
     gfortran
   ];
-  buildInputs = [ lhapdf ];
+  buildInputs = [ lhapdf' ];
 
   cmakeFlags = [
     "-Duse_external_lhapdf=ON"
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index e012505a0156..6ab4fb2e4518 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -12069,14 +12069,6 @@ with pkgs;
 
   ### SCIENCE/PHYSICS
 
-  mcfm = callPackage ../applications/science/physics/MCFM {
-    stdenv = gccStdenv;
-    lhapdf = lhapdf.override {
-      stdenv = gccStdenv;
-      python3 = null;
-    };
-  };
-
   xflr5 = libsForQt5.callPackage ../applications/science/physics/xflr5 { };
 
   ### SCIENCE/LOGIC

From f0500ffd867ea4f285787e4075e4d8b8b558c46f Mon Sep 17 00:00:00 2001
From: Guy Chronister <guychronister@outlook.com>
Date: Mon, 16 Feb 2026 13:47:20 -0600
Subject: [PATCH 2/2] mcfm: modernize derivation

---
 pkgs/by-name/mc/{MCFM => mcfm}/package.nix | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
 rename pkgs/by-name/mc/{MCFM => mcfm}/package.nix (84%)

diff --git a/pkgs/by-name/mc/MCFM/package.nix b/pkgs/by-name/mc/mcfm/package.nix
similarity index 84%
rename from pkgs/by-name/mc/MCFM/package.nix
rename to pkgs/by-name/mc/mcfm/package.nix
index 4ed8058f37d2..ef149b53a875 100644
--- a/pkgs/by-name/mc/MCFM/package.nix
+++ b/pkgs/by-name/mc/mcfm/package.nix
@@ -13,13 +13,13 @@ let
     python3 = null;
   };
 in
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "MCFM";
   version = "10.0.1";
 
   src = fetchurl {
-    url = "https://mcfm.fnal.gov/downloads/${pname}-${version}.tar.gz";
-    sha256 = "sha256-3Dg4KoILb0XhgGkzItDh/1opCtYrrIvtbuALYqPUvE8=";
+    url = "https://mcfm.fnal.gov/downloads/MCFM-${finalAttrs.version}.tar.gz";
+    hash = "sha256-3Dg4KoILb0XhgGkzItDh/1opCtYrrIvtbuALYqPUvE8=";
   };
 
   postPatch = ''
@@ -50,4 +50,4 @@ stdenv.mkDerivation rec {
     maintainers = with lib.maintainers; [ veprbl ];
     platforms = lib.platforms.x86_64;
   };
-}
+})