Services

Online payments, integrated end to end

Taking the money is the easy half — reconciling it, refunding it and passing an audit is where engineering earns its fee.

Accepting a card online takes an afternoon with any modern gateway; the demo is deceptive. The real project is everything around the happy path: strong customer authentication under European PSD2 rules, failed and abandoned payments recovered instead of lost, refunds and chargebacks flowing back into your books, subscriptions that retry intelligently when a card expires, and every transaction reconciling automatically against payouts in your accounting. We integrate Stripe, PayPal, Adyen and regional processors into shops, SaaS products and booking platforms for European clients, and we design for the finance team as much as the customer: when your accountant closes the month, gateway, bank and ledger must already agree. Currency handling, VAT treatment and invoice generation are part of the same build, not follow-up surprises.

Let’s talk about your project

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office@northdan.com · +40 752 070 247

What you get

Conversion-first checkout

Local payment methods, saved cards and one-page flows tuned per market — small checkout frictions compound into large revenue differences.

SCA and PSD2 without drop-off

Authentication exemptions applied where the rules allow, 3-D Secure only when required — compliant and measurably gentler on conversion.

Reconciliation automated

Payouts, fees, refunds and chargebacks map automatically to your invoices and ledger — month-end takes minutes, not a spreadsheet safari.

What we integrate in practice

Card payments with strong customer authentication tuned so that genuine buyers are not lost at the verification step, local European methods where they dominate — bank transfer schemes, wallets, deferred payment — subscriptions with intelligent retry and dunning, and refunds and partial refunds flowing back through the same books rather than around them.

On the finance side we wire settlements into your accounting so that gateway payouts, bank lines and ledger entries reconcile without a human comparing spreadsheets, generate compliant invoices in the right currency and VAT treatment, and expose a view your controller can use during the month-end close. Checkout conversion and clean books are the same project; separating them is how merchants end up with neither.

Frequently asked questions

Which payment provider should we choose?

Depends on markets and model: Stripe for developer speed and subscriptions, Adyen for multi-country volume, plus local methods where you sell. We compare real fee schedules against your transaction profile before recommending.

Can you add subscriptions to our existing product?

Yes — plans, trials, upgrades with proration, dunning for failed renewals and EU VAT invoicing integrate into an existing codebase without a platform rewrite in most cases.

How do you handle card data security?

By architecture: card data goes straight from the customer’s browser to the gateway via tokenised fields and never touches your servers, so your application stores a token rather than a card number. Your own PCI DSS obligations are then confirmed with your acquirer.