diff --git a/.config/nvim/ftplugin/haskell.lua b/.config/nvim/ftplugin/haskell.lua
index 9a1eb6f3..ee1dba9a 100644
--- a/.config/nvim/ftplugin/haskell.lua
+++ b/.config/nvim/ftplugin/haskell.lua
@@ -3,3 +3,6 @@ opts.matchit_let_in()
 
 vim.bo.shiftwidth = 2
 vim.bo.expandtab = true
+
+-- useful for CPP extension
+vim.o.smartindent = true