Payment Gateway Integration

Description

Your site already works. It just cannot take money yet. I put in one gateway: Xendit, DOKU, Midtrans, or Flip. Before anything is charged, the amount is recalculated on my server, so a price sent by the browser never gets used. The webhook is locked down with signature verification, and a notification arriving twice will not charge or ship the same order again. Sometimes the notification never turns up at all. That does happen, and I build the path that finds the payment anyway.

Details

This one is for a site that already exists. If the store itself still needs building, take the website build. If you need both at once, take the bundle.

### Included

• One gateway only: Xendit, DOKU, Midtrans, or Flip. Which one, we settle at the first call.
• The channels you actually need: virtual account, e-wallet, QRIS, retail outlet, or card.
• Amounts recalculated on the server. A price sent by the browser is ignored.
• Webhooks with signature verification. If the same notification arrives twice, that order will not be charged or shipped twice.
• Recovery for payments whose notification never arrives. Gateway notifications do go missing, and without this you hear about it from a customer who has already paid.
• Order states wired all the way through: waiting, paid, expired, failed. Stock that was held returns on its own the moment a payment dies.
• Payment instructions saved onto the order record. Someone who closed the tab at lunch can still pay that evening.
• Everything built against sandbox first. You test each channel, and only once you say it works does it move to production.

### If your buyers are abroad

The right gateway depends on where your company is registered, not where your customers live. Stripe is the one worth knowing about: its Indonesian accounts take rupiah and pay out rupiah, with no cross-border support. Plenty of people assume it solves this. For an Indonesian company, it does not.

I have shipped the four above myself. Anything else we settle at the first call, and I will tell you straight whether I have run it before or would be learning it on your budget.

### Not included

• Merchant registration and KYC. The account stays in your name, and so does the money.
• Gateway transaction fees and settlement.
• A second gateway. I price that as its own job.
• A refunds screen in your admin.
• Cross-border tax. A gateway moves money; it does not register you for EU VAT or US sales tax. If you sell to consumers overseas, that is a merchant-of-record decision, and we talk it through before you commit to anything.
• Any change to how your site looks. What I work on is the plumbing, not the design.