return {
  "jose-elias-alvarez/null-ls.nvim",
  config = function()
    local null_ls     = require("null-ls")

    local formatting  = null_ls.builtins.formatting  -- to setup formatters
    local diagnostics = null_ls.builtins.diagnostics -- to setup linters

    local augroup     = vim.api.nvim_create_augroup("LspFormatting", {})

    null_ls.setup({
      sources = {
        formatting.prettierd,
        diagnostics.eslint_d
      },
      on_attach = function(current_client, bufnr)
        if current_client.supports_method("textDocument/formatting") then
          vim.api.nvim_clear_autocmds({ group = augroup, buffer = bufnr })
          vim.api.nvim_create_autocmd("BufWritePre", {
            group = augroup,
            buffer = bufnr,
            callback = function()
              vim.lsp.buf.format({
                filter = function(client)
                  --  only use null-ls for formatting instead of lsp server
                  return client.name == "null-ls"
                end,
                bufnr = bufnr,
              })
            end,
          })
        end
      end
    })
  end
}