diff --git a/pkgs/applications/networking/browsers/firefox/wrapper.nix b/pkgs/applications/networking/browsers/firefox/wrapper.nix
index 378fe1f4039b..06bd49facb81 100644
--- a/pkgs/applications/networking/browsers/firefox/wrapper.nix
+++ b/pkgs/applications/networking/browsers/firefox/wrapper.nix
@@ -15,6 +15,7 @@
 , pciutils
 , sndio
 , libjack2
+, speechd
 }:
 
 ## configurability of the wrapper itself
@@ -82,6 +83,7 @@ let
             ++ lib.optional sndioSupport sndio
             ++ lib.optional jackSupport libjack2
             ++ lib.optional smartcardSupport opensc
+            ++ lib.optional (cfg.speechSynthesisSupport or false) speechd
             ++ pkcs11Modules;
       gtk_modules = [ libcanberra-gtk3 ];