await new Promise((resolve, reject) => fs.writeFile(filePath + '.dew.js', dewTransform, err => err ? reject(err) : resolve()));
return new Promise((resolve, reject) => fs.writeFile(path.resolve(dir, file), esmWrapperSource, err => err ? reject(err) : resolve())
await new Promise((resolve, reject) => fs.writeFile(dewPath, dewTransform, err => err ? reject(err) : resolve(result)));