From 50779b6ae83f3e0cd317a28f4ef38f83d0a04750 Mon Sep 17 00:00:00 2001
From: Harinn <prinn.dev@pm.me>
Date: Sat, 23 May 2026 23:47:07 +0700
Subject: [PATCH] python3Packages.monosat: fix build with cython 3.1

---
 pkgs/by-name/mo/monosat/package.nix | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkgs/by-name/mo/monosat/package.nix b/pkgs/by-name/mo/monosat/package.nix
index 7d5bea0a95d9..4ae627accfb3 100644
--- a/pkgs/by-name/mo/monosat/package.nix
+++ b/pkgs/by-name/mo/monosat/package.nix
@@ -116,7 +116,11 @@ let
       # the sourceRoot if it weren't for the patch.
       postPatch =
         commonPostPatch
+        # cython 3.1 dropped the python 2 `long` builtin
         + ''
+          substituteInPlace src/monosat/api/python/monosat/monosat_p.pyx \
+            --replace-fail '(int, long)' 'int' \
+            --replace-fail '(int,long)' 'int'
           cd src/monosat/api/python
         ''
         +