STACKHAL FIELD NOTES
Practical guides for the parts of the web that usually break quietly.
Short, evidence-led explainers for email authentication, DNS, technical SEO, and developer infrastructure.
APPLE WALLET · 7 MIN READ
PKPass Signature Errors: What to Check Before Rebuilding the Bundle
Diagnose PKPass signatures by checking ZIP structure, manifest SHA-1 hashes, detached PKCS#7, and certificates.
Read the guide →DNS · 8 MIN READ
DNS Delegation Explained: From Root to Authoritative Nameserver
Follow a DNS lookup across recursive resolution, delegation, glue, authoritative data, and DNSSEC.
Read the guide →REVERSE PROXIES · 9 MIN READ
Nginx to Caddy Migration: Common Rewrite Rules and Hidden Traps
A practical migration guide with real equivalents for locations, proxy_pass, redirects, headers, and path prefixes.
Read the guide →EMAIL AUTHENTICATION · 8 MIN READ
BIMI Not Working? A Practical Guide to DMARC, SVG Tiny PS, DNS Records, and VMC
Diagnose DMARC enforcement, SVG Tiny PS, DNS records, HTTPS hosting, and VMC or CMC certificate requirements.
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