diff --git a/pkgs/development/r-modules/default.nix b/pkgs/development/r-modules/default.nix
index ef32f8b09c17..53323e766313 100644
--- a/pkgs/development/r-modules/default.nix
+++ b/pkgs/development/r-modules/default.nix
@@ -759,6 +759,7 @@ let
     RITCH = [ pkgs.zlib.dev ];
     RcppMeCab = [ pkgs.mecab ];
     PING = [ pkgs.gsl ];
+    PROJ = [ pkgs.proj.dev ];
     RcppAlgos = [ pkgs.gmp.dev ];
     RcppBigIntAlgos = [ pkgs.gmp.dev ];
     spaMM = [ pkgs.gsl ];