Complete the CAPTCHA below by computing a SHA-256 proof-of-work (takes ~5 seconds) or paying 3 sats via Lightning.
# Install via npm npm install @powforge/captcha
<!-- Or add via CDN -->
<script src="https://unpkg.com/@powforge/captcha/dist/powforge-captcha.min.js"
data-target="[data-powforge-captcha]"
data-server="https://captcha.powforge.dev"
data-theme="dark"
data-callback="onCaptchaDone">
</script>
<!-- Place this where you want the widget -->
<div data-powforge-captcha></div>
<!-- Hidden token field (auto-filled) -->
<input type="hidden" name="pf_token">
<script>
function onCaptchaDone(token, method) {
// token = short-lived JWT
// method = 'pow' | 'lightning'
console.log('Verified via', method);
document.getElementById('submit-btn').disabled = false;
}
</script>
// Node.js example
const res = await fetch('https://powforge.dev/captcha/api/verify-token', {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify({ token: req.body.pf_token })
});
const { valid } = await res.json();
if (!valid) return res.status(403).send('CAPTCHA failed');