return {
  {
    "neovim/nvim-lspconfig",
    dependencies = {
      "williamboman/mason.nvim",
      "williamboman/mason-lspconfig.nvim",
      "saghen/blink.cmp",
      "nvim-telescope/telescope-ui-select.nvim",
      "nvimtools/none-ls.nvim",
      'nvim-treesitter/nvim-treesitter',
      'nvim-tree/nvim-web-devicons',
      "jay-babu/mason-null-ls.nvim",
    },
    config = function()
      -- setup --

      local capabilities = vim.lsp.protocol.make_client_capabilities()
      capabilities = vim.tbl_deep_extend('force', capabilities, require('blink.cmp').get_lsp_capabilities({}, false))

      -- mason --

      require("mason").setup({
        PATH = "append",
        ui = {
          border = "rounded",
          icons = {
            package_installed = "✔",
            package_pending = "➜",
            package_uninstalled = "✘"
          }
        }
      })

      -- mason lspconfig --

      require("mason-lspconfig").setup({
        ensure_installed = {
          "lua_ls",
          "clangd",
          "rust_analyzer",
        },
        handlers = {
          -- The first entry (without a key) will be the default handler
          -- and will be called for each installed server that doesn't have
          -- a dedicated handler.
          function(server_name) -- default handler (optional)
            require("lspconfig")[server_name].setup {
              capabilities = capabilities
            }
          end,
          clangd = function()
            require("lspconfig").clangd.setup {
              capabilities = capabilities,
              on_attach = function(client)
                client.server_capabilities.documentFormattingProvider = false
                client.server_capabilities.documentRangeFormattingProvider = false
              end,
            }
          end,
        }
      })

      -- telescope ui for null-ls

      require("telescope").setup {
        extensions = {
          ["ui-select"] = {
          }
        }
      }
      require("telescope").load_extension("ui-select")


      -- null-ls (none-ls)

      local null_ls = require('null-ls')
      require("null-ls").setup({
        sources = {
          null_ls.builtins.diagnostics.trail_space.with {
            disabled_filetypes = { "lua" }
          },
          null_ls.builtins.diagnostics.sqlfluff.with({
            extra_args = { "--dialect", "sqlite" },
          }),
          null_ls.builtins.formatting.sqlfluff.with({
            extra_args = { "--dialect", "sqlite" },
          }),
          null_ls.builtins.formatting.clang_format.with({
            extra_args = { "-style={BasedOnStyle: llvm, IndentWidth: 2, BreakBeforeBraces: Linux, ColumnLimit: 0}" }
          })
        },
      })

      require("mason-null-ls").setup({
        ensure_installed = { "clang_format", "shellharden", "shfmt" }
      })

      -- config --

      vim.diagnostic.config({
        update_in_insert = true,
        signs = { text = { [vim.diagnostic.severity.ERROR] = "✘ ", [vim.diagnostic.severity.WARN] = " ", [vim.diagnostic.severity.HINT] = " ", [vim.diagnostic.severity.INFO] = " " } },
        float = {
          focusable = false,
          style = "minimal",
          border = "rounded",
          source = "always",
          header = "",
          prefix = "",
        },
        virtual_text = {
          prefix = '●', -- Could be '●', '■', 'x', '▎', or anything else
        },
      })
    end,
  }
}