default() {
        return {
            cacheDirectory: true,
            presets: [
                ['@babel/preset-env', { modules: false, forceAllTransforms: true }]
            ],
            plugins: [
                '@babel/plugin-syntax-dynamic-import',
                '@babel/plugin-proposal-object-rest-spread',
                [
                    '@babel/plugin-transform-runtime',
                    {
                        helpers: false
                    }
                ]
            ]
        };
    }
Fetch the default Babel configuration.

@internal
@returns {BabelOptions}