diff --git a/pkgs/by-name/st/stalwart-mail/package.nix b/pkgs/by-name/st/stalwart-mail/package.nix
index 0a9ed8b7d733..16f984cb86c1 100644
--- a/pkgs/by-name/st/stalwart-mail/package.nix
+++ b/pkgs/by-name/st/stalwart-mail/package.nix
@@ -9,6 +9,7 @@
   sqlite,
   foundationdb,
   zstd,
+  rust-jemalloc-sys,
   stdenv,
   nix-update-script,
   nixosTests,
@@ -43,6 +44,7 @@ rustPlatform.buildRustPackage rec {
     openssl
     sqlite
     zstd
+    rust-jemalloc-sys
   ] ++ lib.optionals (stdenv.hostPlatform.isLinux && withFoundationdb) [ foundationdb ];
 
   # Issue: https://github.com/stalwartlabs/mail-server/issues/1104