diff --git a/flake.nix b/flake.nix
index e5e635a223..420f4c70df 100644
--- a/flake.nix
+++ b/flake.nix
@@ -367,6 +367,7 @@
                   "-threaded"
                   # "-debug"
                   "-optl-lffi"
+                  "-optl-lHSrts_thr"
                 ]
                 # This is fairly idiotic. LLD will strip out foreign exported
                 # symbols (a GHC bug? Codegen bug?). So we need to pass `-u <sym>`
@@ -391,6 +392,8 @@
                   "chat_valid_name"
                   "chat_json_length"
                   "chat_write_file"
+                  # We also need to keep the rts init method around.
+                  "hs_init_with_rtsopts"
                 ];
                 postInstall = ''
                   set -x