Cyber security
Website Security Basics: What to Check on Your Business Domain
Your website works, but that only tells you so much. Here’s what to check across HTTPS, DNS, email authentication and publicly exposed services.
11 min read
Articles
Technical guides, engineering notes and practical references from the systems we are building at Ironfang.
Peppol
Understanding EN 16931 Validation Errors
EN 16931 validation errors look cryptic until you know what the rule IDs, business terms and VAT rule families actually mean. Here's how to read them and work out what your invoice is doing wrong.
12 min read
Peppol
How Peppol Invoice Validation Actually Works
Peppol validation is not one check. Your invoice goes through XML, UBL, EN 16931, Peppol and sometimes country-specific rules. Here is what each layer actually does.
11 min read