diff --git a/shell.nix b/shell.nix
index 858e68b9..c091f175 100644
--- a/shell.nix
+++ b/shell.nix
@@ -6,4 +6,5 @@ in
     buildInputs = with pkgs; [
       llvm_10 clang_10 cargo rustc libffi libxml2 clippy
     ];
+    LLVM_SYS_100_PREFIX="${pkgs.llvm_10}";
   }