diff --git a/init.lua b/init.lua
index ada6139..2514f9e 100644
--- a/init.lua
+++ b/init.lua
@@ -1,4 +1,2 @@
 -- bootstrap lazy.nvim, LazyVim and your plugins
 require("config.lazy")
-vim.g.copilot_no_tab_map = true
-vim.api.nvim_set_keymap("i", "<C-Tab>", 'copilot#Accept("<CR>")', { silent = true, expr = true })
diff --git a/lua/config/lsp.lua b/lua/config/lsp.lua
new file mode 100644
index 0000000..5383582
--- /dev/null
+++ b/lua/config/lsp.lua
@@ -0,0 +1,31 @@
+local null_ls = require("null-ls")
+
+local no_really = {
+  method = null_ls.methods.DIAGNOSTICS,
+  filetypes = { "markdown", "text", "tex" },
+  generator = {
+    fn = function(params)
+      local diagnostics = {}
+      -- sources have access to a params object
+      -- containing info about the current file and editor state
+      for i, line in ipairs(params.content) do
+        local col, end_col = line:find("really")
+        if col and end_col then
+          -- null-ls fills in undefined positions
+          -- and converts source diagnostics into the required format
+          table.insert(diagnostics, {
+            row = i,
+            col = col,
+            end_col = end_col + 1,
+            source = "no-really",
+            message = "Don't use 'really!'",
+            severity = vim.diagnostic.severity.WARN,
+          })
+        end
+      end
+      return diagnostics
+    end,
+  },
+}
+
+null_ls.register(no_really)