diff --git a/pkgs/development/r-modules/default.nix b/pkgs/development/r-modules/default.nix
index ae23b32b71a..067db74663e 100644
--- a/pkgs/development/r-modules/default.nix
+++ b/pkgs/development/r-modules/default.nix
@@ -379,6 +379,7 @@ let
   packagesWithBuildInputs = {
     # sort -t '=' -k 2
     gam = lib.optionals stdenv.isDarwin [ pkgs.libiconv ];
+    RcppArmadillo = lib.optionals stdenv.isDarwin [ pkgs.libiconv ];
     quantreg = lib.optionals stdenv.isDarwin [ pkgs.libiconv ];
     rmutil = lib.optionals stdenv.isDarwin [ pkgs.libiconv ];
     robustbase = lib.optionals stdenv.isDarwin [ pkgs.libiconv ];