Finnish shoppers overwhelmingly expect to pay by their own bank's online payment button (verkkomaksu) — OP, Nordea, Danske, S-Pankki, Aktia and the rest — alongside cards and mobile wallets like MobilePay. Paytrail aggregates all of those methods behind a single integration, but Odoo core ships no Paytrail payment provider. Out of the box you get Stripe, Adyen, PayPal, and a handful of others, none of which surface the Finnish bank-button experience your customers look for at checkout. The usual workarounds — pushing buyers to a manual bank transfer, or bolting on a generic redirect — cost you conversions and leave settlement reconciliation to spreadsheets.

ECOSIRE builds a first-class Odoo payment provider (payment.provider / payment.transaction) that speaks Paytrail's aggregation API natively. We register a new provider record with its own code, credentials fields (merchant ID and secret key stored via Odoo settings, never hardcoded), and a payment flow that requests Paytrail's available payment groups so your customers see the live list of bank buttons, card, and wallet options rendered inside the standard eCommerce and invoicing checkout. On submission we create a Paytrail payment, redirect the buyer to complete it, and land them back on Odoo's return controller.

The security-critical part is the callback. Every Paytrail response and webhook carries an HMAC signature over the checkout-* header set and body; our controller recomputes that signature server-side with your secret key and rejects any request whose signature does not match before a single payment.transaction is confirmed. That closes the door on spoofed "paid" callbacks — a transaction only moves to done on a verified, authentic success signal. Refunds are wired through Paytrail's refund endpoint from the transaction form, so a full or partial refund initiated in Odoo calls back with its own verified confirmation. Amounts are handled in EUR with correct minor-unit conversion, and the provider is delivered for Odoo 17.0, 18.0, or 19.0 with the API and controller differences between those versions handled per target.

Because this is BUILD-TO-ORDER, you are not downloading a pre-built app. After you request a quotation we run a short scoping call to confirm your Odoo version and edition (Community or Enterprise), which Paytrail account and methods you need, and how you want settlement and refunds to behave. Typical delivery is 2-4 weeks from confirmed scope. You receive the installable source for your exact version, UAT on a staging database against Paytrail's test credentials, and a defined post-go-live support window — no guesswork, no fabricated benchmarks.