diff --git a/pkgs/development/python-modules/rtoml/default.nix b/pkgs/development/python-modules/rtoml/default.nix
index e5043ca941a0..9ff43bce0843 100644
--- a/pkgs/development/python-modules/rtoml/default.nix
+++ b/pkgs/development/python-modules/rtoml/default.nix
@@ -5,6 +5,7 @@
 , setuptools-rust
 , rustPlatform
 , pytestCheckHook
+, libiconv
 }:
 
 buildPythonPackage rec {
@@ -32,6 +33,8 @@ buildPythonPackage rec {
     cargoSetupHook
   ];
 
+  buildInputs = [ libiconv ];
+
   pythonImportsCheck = [ "rtoml" ];
 
   checkInputs = [ pytestCheckHook ];