diff --git a/doc/fugitive-ts.nvim.txt b/doc/fugitive-ts.nvim.txt
index a825909..f91fb09 100644
--- a/doc/fugitive-ts.nvim.txt
+++ b/doc/fugitive-ts.nvim.txt
@@ -34,6 +34,10 @@ SETUP                                                        *fugitive-ts-setup*
 
       -- Debounce delay in ms (default: 50)
       debounce_ms = 50,
+
+      -- Max lines per hunk before skipping treesitter (default: 500)
+      -- Prevents lag on large diffs
+      max_lines_per_hunk = 500,
     })
 <
 
diff --git a/lua/fugitive-ts/highlight.lua b/lua/fugitive-ts/highlight.lua
index c77a3fa..ea292d0 100644
--- a/lua/fugitive-ts/highlight.lua
+++ b/lua/fugitive-ts/highlight.lua
@@ -10,13 +10,27 @@ end
 ---@param bufnr integer
 ---@param ns integer
 ---@param hunk fugitive-ts.Hunk
+---@param max_lines integer
 ---@param debug? boolean
-function M.highlight_hunk(bufnr, ns, hunk, debug)
+function M.highlight_hunk(bufnr, ns, hunk, max_lines, debug)
   local lang = hunk.lang
   if not lang then
     return
   end
 
+  if #hunk.lines > max_lines then
+    if debug then
+      dbg(
+        'skipping hunk %s:%d (%d lines > %d max)',
+        hunk.filename,
+        hunk.start_line,
+        #hunk.lines,
+        max_lines
+      )
+    end
+    return
+  end
+
   ---@type string[]
   local code_lines = {}
   for _, line in ipairs(hunk.lines) do
@@ -52,6 +66,18 @@ function M.highlight_hunk(bufnr, ns, hunk, debug)
     return
   end
 
+  for i, line in ipairs(hunk.lines) do
+    local buf_line = hunk.start_line + i - 1
+    local line_len = #line
+    if line_len > 1 then
+      pcall(vim.api.nvim_buf_set_extmark, bufnr, ns, buf_line, 1, {
+        end_col = line_len,
+        hl_group = 'Normal',
+        priority = 199,
+      })
+    end
+  end
+
   local extmark_count = 0
   for id, node, _ in query:iter_captures(trees[1]:root(), code) do
     local capture_name = '@' .. query.captures[id]
diff --git a/lua/fugitive-ts/init.lua b/lua/fugitive-ts/init.lua
index 8bd4977..e6de719 100644
--- a/lua/fugitive-ts/init.lua
+++ b/lua/fugitive-ts/init.lua
@@ -3,6 +3,7 @@
 ---@field debug boolean
 ---@field languages table<string, string>
 ---@field debounce_ms integer
+---@field max_lines_per_hunk integer
 
 ---@class fugitive-ts
 ---@field attach fun(bufnr?: integer)
@@ -21,6 +22,7 @@ local default_config = {
   debug = false,
   languages = {},
   debounce_ms = 50,
+  max_lines_per_hunk = 500,
 }
 
 ---@type fugitive-ts.Config
@@ -54,7 +56,7 @@ local function highlight_buffer(bufnr)
   local hunks = parser.parse_buffer(bufnr, config.languages, config.debug)
   dbg('found %d hunks in buffer %d', #hunks, bufnr)
   for _, hunk in ipairs(hunks) do
-    highlight.highlight_hunk(bufnr, ns, hunk, config.debug)
+    highlight.highlight_hunk(bufnr, ns, hunk, config.max_lines_per_hunk, config.debug)
   end
 end
 
@@ -101,6 +103,14 @@ function M.attach(bufnr)
     callback = debounced,
   })
 
+  vim.api.nvim_create_autocmd('Syntax', {
+    buffer = bufnr,
+    callback = function()
+      dbg('syntax event, re-highlighting buffer %d', bufnr)
+      highlight_buffer(bufnr)
+    end,
+  })
+
   vim.api.nvim_create_autocmd('BufWipeout', {
     buffer = bufnr,
     callback = function()