diff --git a/init.lua b/init.lua
index 6e61836..17b9fae 100644
--- a/init.lua
+++ b/init.lua
@@ -417,7 +417,9 @@ local plugins = {
         }
     },
     { 'Civitasv/cmake-tools.nvim' },
-    { 'p00f/cphelper.nvim' }
+    { 'p00f/cphelper.nvim' },
+    { "savq/melange-nvim" },
+    { 'hrsh7th/vim-vsnip' }
 }
 local opts = { 
 }
@@ -469,7 +471,8 @@ require("monokai-pro").setup({
   },
 })
 
-vim.cmd([[colorscheme monokai-pro]])
+-- vim.cmd([[colorscheme monokai-pro]])
+vim.cmd([[colorscheme melange]])
 
 local builtin = require("telescope.builtin")
 vim.keymap.set('n', '<leader>p', builtin.find_files, {})
@@ -498,21 +501,47 @@ end
 
 vim.opt.completeopt = "menu,menuone,noselect"
 
+local has_words_before = function()
+  unpack = unpack or table.unpack
+  local line, col = unpack(vim.api.nvim_win_get_cursor(0))
+  return col ~= 0 and vim.api.nvim_buf_get_lines(0, line - 1, line, true)[1]:sub(col, col):match("%s") == nil
+end
+
+local feedkey = function(key, mode)
+  vim.api.nvim_feedkeys(vim.api.nvim_replace_termcodes(key, true, true, true), mode, true)
+end
+
 cmp.setup({
   snippet = {
     expand = function(args)
       luasnip.lsp_expand(args.body)
     end,
   },
-  mapping = cmp.mapping.preset.insert({
-    ["<C-k>"] = cmp.mapping.select_prev_item(), -- previous suggestion
-    ["<C-j>"] = cmp.mapping.select_next_item(), -- next suggestion
-    ["<C-b>"] = cmp.mapping.scroll_docs(-4),
-    ["<C-f>"] = cmp.mapping.scroll_docs(4),
-    ["<C-Space>"] = cmp.mapping.complete(), -- show completion suggestions
-    ["<ESC>"] = cmp.mapping.abort(), -- close completion window
-    ["<tab>"] = cmp.mapping.confirm({ select = true }),
-  }),
+  mapping = {
+    ["<Tab>"] = cmp.mapping(function(fallback)
+      if cmp.visible() then
+        cmp.confirm({ select = true })
+      elseif luasnip_status and luasnip.expand_or_jumpable() then
+        luasnip.expand_or_jump()
+      elseif has_words_before() then
+        cmp.complete()
+      else
+        fallback()
+      end
+    end, { "i", "s" }),
+
+    ["<S-Tab>"] = cmp.mapping(function()
+      if cmp.visible() then
+        cmp.select_prev_item()
+      elseif vim.fn["vsnip#jumpable"](-1) == 1 then
+        feedkey("<Plug>(vsnip-jump-prev)", "")
+      end
+    end, { "i", "s" }),
+
+    ['<C-k>'] = cmp.mapping.select_prev_item(),
+    ['<C-j>'] = cmp.mapping.select_next_item(),
+    ['<ESC>'] = cmp.mapping.abort(),
+  },
   -- sources for autocompletion
   sources = cmp.config.sources({
     { name = "nvim_lsp" }, -- LSP