return {
    {
        "williamboman/mason.nvim",
        opts = function(_, opts)
            opts.ensure_installed = opts.ensure_installed or {}
            vim.list_extend(opts.ensure_installed, { "buf", "buf-language-server" })
        end,
    },
    {
        "nvimtools/none-ls.nvim",
        opts = function(_, opts)
            local nls = require("null-ls")
            opts.sources = vim.list_extend(opts.sources or {}, {
                nls.builtins.diagnostics.buf,
                nls.builtins.formatting.buf,
            })
        end,
    },
}