diff --git a/pkgs/development/python-modules/graph-tool/default.nix b/pkgs/development/python-modules/graph-tool/default.nix
index 2aa1d5737b71..2f49c1e56803 100644
--- a/pkgs/development/python-modules/graph-tool/default.nix
+++ b/pkgs/development/python-modules/graph-tool/default.nix
@@ -2,10 +2,9 @@
   buildPythonPackage,
   lib,
   fetchurl,
-  fetchpatch,
   stdenv,
 
-  boost189,
+  boost191,
   cairomm,
   cgal,
   expat,
@@ -31,17 +30,7 @@
 }:
 
 let
-  boost' = boost189.override {
-    patches = [
-      # required to build against Clang >= 21 (https://github.com/boostorg/lexical_cast/pull/87)
-      # TODO: drop when upgrading to Boost >= 1.90
-      (fetchpatch {
-        name = "Reduce-dependency-on-Boost.TypeTraits-now-that-C-11-.patch";
-        url = "https://github.com/boostorg/lexical_cast/commit/8fc8a19931c8cb452400af907959fdacbbdd8ec1.patch";
-        relative = "include";
-        hash = "sha256-OO39ejR+I5ufjqinrMJ6HgjTE7Ph+XBu50PqcIKaIQo=";
-      })
-    ];
+  boost' = boost191.override {
     enablePython = true;
     inherit python;
   };