diff --git a/pkgs/os-specific/darwin/CoreSymbolication/default.nix b/pkgs/os-specific/darwin/CoreSymbolication/default.nix
index 5cf92a41a6f83..d9a2b378134a2 100644
--- a/pkgs/os-specific/darwin/CoreSymbolication/default.nix
+++ b/pkgs/os-specific/darwin/CoreSymbolication/default.nix
@@ -1,4 +1,4 @@
-{ lib, fetchFromGitHub, stdenv }:
+{ lib, fetchFromGitHub, fetchpatch, stdenv }:
 
 stdenv.mkDerivation {
   pname = "core-symbolication";
@@ -11,6 +11,15 @@ stdenv.mkDerivation {
     hash = "sha256-PzvLq94eNhP0+rLwGMKcMzxuD6MlrNI7iT/eV0obtSE=";
   };
 
+  patches = [
+    # C99 compilation fix
+    # https://github.com/matthewbauer/CoreSymbolication/pull/1
+    (fetchpatch {
+      url = "https://github.com/boltzmannrain/CoreSymbolication/commit/1c26cc93f260bda9230a93e91585284e80aa231f.patch";
+      hash = "sha256-d/ieDEnvZ9kVOjBVUdJzGmdvC1AF3Jk4fbwp04Q6l/I=";
+    })
+  ];
+
   makeFlags = [ "PREFIX=$(out)" "CC=${stdenv.cc.targetPrefix}cc" ];
 
   meta = with lib; {