diff --git a/lua/troy0820/lazy/lsp.lua b/lua/troy0820/lazy/lsp.lua
index 956f451..7251aa1 100644
--- a/lua/troy0820/lazy/lsp.lua
+++ b/lua/troy0820/lazy/lsp.lua
@@ -18,6 +18,38 @@ return {
     lsp_zero.on_attach(function(client, bufnr)
       lsp_zero.default_keymaps({ buffer = bufnr })
     end)
+    local buffer_autoformat = function(bufnr)
+      local group = 'lsp_autoformat'
+      vim.api.nvim_create_augroup(group, { clear = false })
+      vim.api.nvim_clear_autocmds({ group = group, buffer = bufnr })
+
+      vim.api.nvim_create_autocmd('BufWritePre', {
+        buffer = bufnr,
+        group = group,
+        desc = 'LSP format on save',
+        callback = function()
+          -- note: do not enable async formatting
+          vim.lsp.buf.format({ async = false, timeout_ms = 10000 })
+        end,
+      })
+    end
+
+    vim.api.nvim_create_autocmd('LspAttach', {
+      callback = function(event)
+        local id = vim.tbl_get(event, 'data', 'client_id')
+        local client = id and vim.lsp.get_client_by_id(id)
+
+        if client == nil then
+          return
+        end
+
+        -- make sure there is at least one client with formatting capabilities
+        if client.supports_method('textDocument/formatting') then
+          buffer_autoformat(event.buf)
+        end
+      end
+    })
+
 
     require('mason').setup({})
     require('mason-lspconfig').setup({