diff --git a/shell.nix b/shell.nix
index c735f1339..5bc449cda 100644
--- a/shell.nix
+++ b/shell.nix
@@ -13,6 +13,7 @@ mkShell rec {
     harfbuzzWithCoreText
     ncurses
     lcms2
+    librsync
   ] ++ optionals stdenv.isDarwin [
     Cocoa
     CoreGraphics