diff --git a/.config/nvim/lua/lsp/c.lua b/.config/nvim/lua/lsp/c.lua
index e9277c0..986eca3 100644
--- a/.config/nvim/lua/lsp/c.lua
+++ b/.config/nvim/lua/lsp/c.lua
@@ -3,11 +3,18 @@
 -- License       : GPLv3
 -- Description   : clangd config file for lsp
 
+-- The nvim-cmp almost supports LSP's capabilities so You should advertise it to LSP servers..
+local capabilities = vim.lsp.protocol.make_client_capabilities()
+capabilities = require('cmp_nvim_lsp').update_capabilities(capabilities)
+
+
 require("lspconfig").clangd.setup {
         cmd = { "clangd",
                 "--background-index",
                 "--suggest-missing-includes",
                 "--clang-tidy",
                 "--header-insertion=iwyu"
-        }
+        },
+        -- The following example advertise capabilities to `clangd`.
+        capabilities = capabilities,
 }
diff --git a/.config/nvim/lua/lsp/lua.lua b/.config/nvim/lua/lsp/lua.lua
index 11567ec..892afc2 100644
--- a/.config/nvim/lua/lsp/lua.lua
+++ b/.config/nvim/lua/lsp/lua.lua
@@ -21,7 +21,7 @@ require'lspconfig'.sumneko_lua.setup {
                         },
                         diagnostics = {
                                 -- Get the language server to recognize the `vim` global
-                                globals = {'vim'},
+                                globals = {"vim", "use", "globals", "utils"},
                         },
                         workspace = {
                                 -- Make the server aware of Neovim runtime files
diff --git a/.config/nvim/lua/plugin/cmp.lua b/.config/nvim/lua/plugin/cmp.lua
index deebb51..fee7dda 100644
--- a/.config/nvim/lua/plugin/cmp.lua
+++ b/.config/nvim/lua/plugin/cmp.lua
@@ -58,8 +58,8 @@ cmp.setup {
                         select = true,
                 }),
                 ["<Tab>"] = cmp.mapping(function(fallback)
-                        if vim.fn.pumvisible() == 1 then
-                                vim.fn.feedkeys(t "<C-n>", "n")
+                        if cmp.visible() then
+                                cmp.select_next_item()
                         elseif luasnip.expand_or_jumpable() then
                                 luasnip.expand_or_jump()
                         elseif check_backspace() then
@@ -69,8 +69,8 @@ cmp.setup {
                         end
                 end, { "i", "s" }),
                 ["<S-Tab>"] = cmp.mapping(function(fallback)
-                        if vim.fn.pumvisible() == 1 then
-                                vim.fn.feedkeys(t "<C-p>", "n")
+                        if cmp.visible() then
+                                cmp.select_prev_item()
                         elseif luasnip.jumpable(-1) then
                                 luasnip.jump(-1)
                         else
diff --git a/.config/zsh/.zprofile b/.config/zsh/.zprofile
index fc16ab9..53bc915 100644
--- a/.config/zsh/.zprofile
+++ b/.config/zsh/.zprofile
@@ -22,6 +22,8 @@ export ANDROID_PREFS_ROOT="$XDG_CONFIG_HOME/android"
 export GTK2_RC_FILES="$XDG_CONFIG_HOME/gtk-2.0/gtkrc-2.0"
 export TEXMFHOME="$XDG_DATA_HOME/texmf"
 export CARGO_HOME="$XDG_DATA_HOME/cargo"
+export OPAMROOT="$XDG_DATA_HOME/opam"
+export COQBIN="$OPAMROOT/default/bin"
 
 ## default programs
 export GPG_ASKPASS="/usr/bin/pinentry-curses"
diff --git a/.config/zsh/.zshrc b/.config/zsh/.zshrc
index 1247b25..0dbec9e 100644
--- a/.config/zsh/.zshrc
+++ b/.config/zsh/.zshrc
@@ -78,3 +78,6 @@ typeset -A ZSH_HIGHLIGHT_STYLES
 ZSH_HIGHLIGHT_STYLES[alias]='fg=green,bold'
 ZSH_HIGHLIGHT_STYLES[path]='fg=magenta,bold'
 ZSH_HIGHLIGHT_STYLES[unknown-token]='bg=red,fg=white,bold'
+
+# opam configuration
+test -r "$OPAMROOT/opam-init/init.zsh" && . "$OPAMROOT/opam-init/init.zsh" > /dev/null 2> /dev/null || true