code: function migrate(files) {
    files.forEach((file) => {
      let content;
      try {
        content = fs.readFileSync(file, {encoding: 'utf-8'});
      } catch (e) {
        console.error(`\u{1b}[31mProblem reading ${file}: ${e.message}\u{1b}[39m`);
        process.exit(1);
      }
      const newContent = transform(content);
      if (newContent !== content) {
        console.log('Found a file that has things to migrate: ' + file);
        fs.writeFileSync(file, newContent, {encoding: 'utf-8'});
      }
    });
  }
docs: entry point