diff --git a/init.el b/init.el
index 1b19ea9..28c4122 100644
--- a/init.el
+++ b/init.el
@@ -1993,7 +1993,9 @@ MAPS are expected to be keymaps for modes for languages with C-style comments."
 (use-package haskell-ts-mode
   :hook (haskell-ts-mode . my/eglot-if-trusted)
   :custom
-  (haskell-ts-use-indent t))
+  (haskell-ts-use-indent t)
+  :init
+  (add-to-list 'auto-mode-alist '("\\.hs\\'" . haskell-ts-mode)))
 
 ;; c-ts-mode
 (setopt ff-ignore-include t)