M-Pesa & Payments Integration for Kenyan Applications

Most M-Pesa integration guides show you how to fire an STK Push and get a callback. Production is harder than that. What happens when the callback never arrives? What happens when a user pays but your system missed the confirmation? What do you do when Safaricom's API returns a timeout and you don't know if the transaction went through? I integrate M-Pesa Daraja into web and mobile applications — built on Laravel, React/Next.js, and Flutter — and build the reconciliation, retry, and logging infrastructure that keeps payments reliable, not just working in a demo.

STK Push — Lipa Na M-Pesa Online

STK Push lets your application initiate a payment request directly to a customer's phone. The user sees a prompt, enters their PIN, and the money moves. I implement the complete STK Push flow: initiating the request, storing the pending transaction with a reference, handling the callback Safaricom sends to confirm or reject, and giving users immediate feedback without polling.

Callbacks can arrive delayed, duplicated, or not at all. I implement idempotent handlers that process each transaction exactly once regardless of how many times the same callback arrives. Timeout checks flag transactions needing reconciliation when a callback has not arrived within a defined window. An admin dashboard lets your operations team see every transaction's current state and trigger the Safaricom Transaction Status API query for anything ambiguous.

B2C — Bulk Disbursements

B2C sends money from your M-Pesa business account to individual phone numbers. Common uses include paying suppliers, disbursing loans, sending agent commissions, and issuing refunds. I implement B2C with queue management for batches of hundreds or thousands of payments, per-transaction result tracking, and settlement reports your finance team can export directly.

B2C has its own failure taxonomy: insufficient balance, invalid phone numbers, per-transaction limits, and B2C API-specific error codes all need distinct handling. I build the notification layer so your operations team knows exactly which payments settled, which failed definitively, and which need manual investigation.

C2B — Paybill and Buy Goods Collection

C2B lets customers pay your Paybill or Till number through the standard M-Pesa menu and your system receives a notification. I register your confirmation and validation URLs with Safaricom, implement the validation logic that accepts or rejects incoming payments against your business rules, handle the confirmation webhook, and reconcile confirmed payments against your orders or invoices automatically.

USSD Integration

USSD gives feature-phone users access to services without internet — multi-level menu flows that work on any handset over a basic voice connection. I build USSD applications using Africa's Talking or Safaricom's direct USSD gateway, with the session state management that makes multi-level menus reliable: handling timeouts, invalid input, and dropped sessions so users are never left in an inconsistent state. Common use cases include e.g. loan applications, bill payment, account inquiries, and service confirmations.

Other Payment Gateways

Beyond M-Pesa, I integrate Stripe for international card payments and Paystack for broader African coverage. The same reconciliation-first approach applies regardless of the payment method.

What Good Payments Infrastructure Looks Like

Every payment event is logged with the full payload before it is processed. Webhooks are idempotent — processing the same event twice does nothing. Failed payments can be retried with exponential backoff where appropriate. Every transaction has an audit trail from initiation to settlement. A finance export to Excel or CSV can be built in. Alerts can be configured to fire when error rates exceed thresholds you set. None of this is optional — it is how production payments infrastructure needs to be built from day one.