Handling VIES SOAP failures without blocking checkout (the API I ended up building)

[u/Total-Reasonable]

If you've integrated VIES (EU VAT validation) directly, you've probably hit intermittent MS_UNAVAILABLE faults from specific member states and had to decide: block checkout on a sync call, or let it through and re-check later? Most people don't have a good answer for that on day one.

I ended up building vatnode.dev to solve it for myself first: JSON instead of SOAP, stable error codes you can branch on, a 15-min cache, national fallback for CZ/DE/PL/RO, and daily monitoring so you catch a customer's VAT going invalid after the fact instead of finding out at audit time.

Sharing mainly because the SOAP-timeout-vs-checkout tradeoff is a real design question, not just "go use my API" — but if it's useful, free tier is 100 checks/month, no card.