diff --git a/lib/languages.nix b/lib/languages.nix
index c4709442..f4ab1cca 100644
--- a/lib/languages.nix
+++ b/lib/languages.nix
@@ -62,7 +62,7 @@ in {
       };
 
       cmd = mkOption {
-        type = nullOr (listOf (oneOf [str luaInline]));
+        type = nullOr (either luaInline (listOf str));
         default = null;
         description = "Command used to start the LSP server";
       };