I Built a Zero-Dependency Website Change Detector in Node.js (Open Source)

I needed to know when a competitor changed their pricing page. I didn't want to set up Puppeteer, a headless browser, or a paid monitoring tool. So I built a 50-line Node.js script using the SnapAPI analyze endpoint. Here's how it works — and it's fully open source. The core pattern Instead of scraping raw HTML and trying to parse it, SnapAPI's /v1/analyze returns structured data about a page: the primary CTA text, word count, detected tech stack, navigation items. The script saves a snapshot of this data after each run, then diffs it against the previous snapshot on the next run. Here's the key logic: async function analyzeUrl(url) { return new Promise((resolve, reject) => { const endpoint = `https://api.snapapi.tech/v1/analyze?url=${encodeURIComponent(url)}&api_key=${API_KEY}`; const req = https.get(endpoint, (res) => { let body = ''; res.on('data', chunk => { body += chunk; }); res.on('end', () => { if (res.statusCode !== 200) return reject(new Error(`HTTP ${res.stat