Tax Provider apps: let a service that knows tax do the tax

What the tax provider endpoint does

Shopware hands your endpoint the full cart — line items, customer, addresses — and you return the tax per position and the totals. Shopware then displays and stores exactly what you returned. One system decides tax, and everything downstream agrees with it.

When you actually need it

Selling into several EU countries, handling reverse charge, or dealing with reduced rates that depend on the product and the destination. A hard-coded 19% and a rule table will get you through year one and fail an audit in year three.

Latency is now a checkout risk

Every cart recalculation may call your endpoint. Cache aggressively on identical carts, set a hard timeout, and decide in advance what happens when the tax service is down — because it will be, on the busiest day.

Store the answer, not just the number

Keep the full response with the order: rates, jurisdictions, the reason for reverse charge. When a tax auditor asks why order 4711 had 0% VAT two years ago, that stored payload is your entire defence.