The security checks that matter
Confirm payments from the server, not the browser
When a customer finishes paying, they are usually sent back to a "thank you" page. That redirect alone does not prove anything: a dishonest customer could open the same page without paying. A secure integration confirms every payment directly with the payment provider, through the provider's notification (often called a webhook or callback) or by checking the transaction status from your server, before marking an order as paid.
Check the amount and currency
When the confirmation arrives, your website should check that the amount and currency match the order. Otherwise someone could pay 100 FCFA for a 100,000 FCFA order.
Handle pending and failed payments
Mobile Money payments are not always instant. A customer may not see the prompt, may run out of balance or may let the prompt expire. Your website should show clear messages for pending and failed payments, let the customer try again, and never deliver an order until payment is confirmed.
Keep secret keys secret
Your provider gives you API keys. They belong on the server only, never in the website's public code or in screenshots shared on WhatsApp.