> ## Documentation Index
> Fetch the complete documentation index at: https://docs.negentro.tech/llms.txt
> Use this file to discover all available pages before exploring further.

# Webhooks & Real-Time Event System

> HTTP callbacks for memory lifecycle mutations ( memory.created ), CDC data sync completions ( sync.completed ), and BYOK key alerts ( byok.key_failed ) with HMAC-SHA256 signature verification.

## HMAC-SHA256 Signature Verification

```python Python theme={null}
import hmac, hashlib

def verify_webhook(payload_bytes, sig_header, secret):
    computed = hmac.new(secret.encode(), payload_bytes, hashlib.sha256).hexdigest()
    return hmac.compare_digest(f"sha256={computed}", sig_header)
```


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