var fs = require('fs'); var markfile = '.buildmark'; var resolve = process.argv.indexOf('resolve') > -1; if (!resolve) { fs.writeFileSync(markfile, Date.now()); } else { let mark = parseInt(fs.readFileSync(markfile).toString()); console.log(`Build ran in ${(Date.now() - mark)/1000} seconds.`); fs.unlinkSync(markfile); }