Your Domain Is Sending Spam (Spoiler: It's Not You)
How a bounce exposed my SPF/DMARC gap — and how I fixed it in 3 Cloudflare commands
🔧 Tools & Repository
All code from this investigation is available at:
GitHub: 
Tools: MX-Spoof-Checker — dtrh_mail_poc.py (scanner) + dtrh_mail_send.py (demo spoofer)
Source: BLOG_POST.md from the MX-Spoof-Checker repository