return {
  -- lspconfig
  {
    "neovim/nvim-lspconfig",
    event = "BufReadPre",
    dependencies = {
      { "folke/neoconf.nvim", cmd = "Neoconf", config = true },
      { "folke/neodev.nvim", config = true },
      "mason.nvim",
      { "williamboman/mason-lspconfig.nvim", config = { automatic_installation = true } },
      "hrsh7th/cmp-nvim-lsp",
    },
    ---@type lspconfig.options
    servers = nil,
    config = function(plugin)
      -- setup formatting and keymaps
      require("lazyvim.util").on_attach(function(client, buffer)
        require("lazyvim.plugins.lsp.format").on_attach(client, buffer)
        require("lazyvim.plugins.lsp.keymaps").on_attach(client, buffer)
      end)

      -- diagnostics
      for name, icon in pairs(require("lazyvim.config.icons").diagnostics) do
        name = "DiagnosticSign" .. name
        vim.fn.sign_define(name, { text = icon, texthl = name, numhl = "" })
      end
      vim.diagnostic.config({
        underline = true,
        update_in_insert = false,
        virtual_text = { spacing = 4, prefix = "●" },
        severity_sort = true,
      })

      -- lspconfig
      local capabilities = require("cmp_nvim_lsp").default_capabilities(vim.lsp.protocol.make_client_capabilities())

      ---@type lspconfig.options
      local servers = plugin.servers or require("lazyvim.plugins.lsp.servers")
      for server, opts in pairs(servers) do
        opts.capabilities = capabilities
        require("lspconfig")[server].setup(opts)
      end
    end,
  },

  -- formatters
  {
    "jose-elias-alvarez/null-ls.nvim",
    event = "BufReadPre",
    dependencies = { "mason.nvim" },
    config = function()
      local nls = require("null-ls")
      nls.setup({
        sources = {
          -- nls.builtins.formatting.prettierd,
          nls.builtins.formatting.stylua,
          nls.builtins.diagnostics.flake8,
        },
      })
    end,
  },

  -- cmdline tools and lsp servers
  {

    "williamboman/mason.nvim",
    cmd = "Mason",
    keys = { { "<leader>cm", "<cmd>Mason<cr>", desc = "Mason" } },
    ensure_installed = {
      "stylua",
      "shellcheck",
      "shfmt",
      "flake8",
    },
    config = function(plugin)
      require("mason").setup()
      local mr = require("mason-registry")
      for _, tool in ipairs(plugin.ensure_installed) do
        local p = mr.get_package(tool)
        if not p:is_installed() then
          p:install()
        end
      end
    end,
  },
}