diff --git a/pkgs/development/tools/rust/cargo-watch/default.nix b/pkgs/development/tools/rust/cargo-watch/default.nix
index 96c80adae63..b59e5a4d33d 100644
--- a/pkgs/development/tools/rust/cargo-watch/default.nix
+++ b/pkgs/development/tools/rust/cargo-watch/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, lib, rustPlatform, fetchFromGitHub, CoreServices, rust }:
+{ stdenv, lib, rustPlatform, fetchFromGitHub, CoreServices, rust, libiconv }:
 
 rustPlatform.buildRustPackage rec {
   pname = "cargo-watch";
@@ -13,7 +13,7 @@ rustPlatform.buildRustPackage rec {
 
   cargoSha256 = "sha256-6ztMEfVOlsyUtIeH+Qd/l7khC7XOHKc4bWsDd27RNu8=";
 
-  buildInputs = lib.optional stdenv.isDarwin CoreServices;
+  buildInputs = lib.optionals stdenv.isDarwin [ CoreServices libiconv ];
 
   # `test with_cargo` tries to call cargo-watch as a cargo subcommand
   # (calling cargo-watch with command `cargo watch`)