Integrating M-Pesa: A Technical Guide

M-Pesa is essential for any Kenyan business app. Here's how to integrate it properly.

The API

Safaricom provides a REST API (Daraja). You'll need:

• Consumer key and secret
• Short code
• Passkey for Lipa Na M-Pesa Online

The Flow

1. Initiate payment request
2. Customer gets STK push on their phone
3. They enter PIN
4. You receive callback with result
5. Update your records

The Gotchas

Callbacks are not guaranteed: Sometimes they don't arrive. Build a fallback query system.

Testing is painful: Sandbox environment behaves differently from production.

Rate limits exist: Don't hammer the API. Implement backoff and retry logic.

Security

Never expose your API credentials. Use environment variables. Rotate keys regularly.

Validate callback signatures. Safaricom signs all callbacks—verify them.

Worth It?

Absolutely. Cash payments are risky. Bank transfers are slow. M-Pesa is instant and trusted.