What to Ask a Developer Before They Integrate Paystack

A payment integration is not a regular feature. It handles real money. A bug in your blog page is annoying. A bug in your payment flow loses revenue, double-charges customers, or exposes your business to fraud.

Many business owners hire a developer without asking payment-specific questions. They assume any developer who can build a website can handle payments. That is not always true. Building a website and building a secure, reliable payment flow require different skills.

These questions help you tell the difference between a developer who understands payment engineering and one who is going to copy code from a tutorial and hope it works.

Good answer: "Yes, I have built Paystack integrations for [specific projects]. I am familiar with their API, webhook system, and the specific requirements for [your country's payment methods]."

Acceptable answer: "I have not used Paystack specifically, but I have integrated Flutterwave/Stripe/other payment gateways. The concepts are similar and I can review Paystack's documentation."

Red flag answer: "No, but how hard can it be? I will figure it out."

Direct Paystack experience is ideal because each payment gateway has its own quirks, API patterns, and common pitfalls. But experience with other payment gateways is a reasonable foundation. What you want to avoid is someone who has never touched a payment integration and treats it like just another API call.

If the developer has done Paystack work before, ask them to show you a live site they built with Paystack. Even better, ask their previous client about the experience.

This is the single most important technical question. Webhooks are the mechanism Paystack uses to tell your server that a payment succeeded or failed. Without proper webhook handling, your system will miss payments.

Good answer: "I will set up a webhook endpoint that receives Paystack's payment notifications, verifies the signature using your secret key, checks that the amount matches, and updates the order status in your database. The webhook endpoint will return a 200 response immediately to acknowledge receipt."

Red flag answer: "We do not need webhooks. We can just check the redirect URL." or "What are webhooks?"

If a developer does not understand webhooks, they are not qualified to build a payment integration. Full stop. Relying on redirect URLs alone is the number one cause of missed payments in Paystack integrations. Redirects are unreliable. Webhooks are the backbone of payment confirmation.

This one question eliminates most unqualified developers.

Payments fail regularly. Cards get declined. Networks time out. Banks go down. The question is: what does the customer see when this happens?

Good answer: "When a payment fails, the customer sees a clear error message explaining what happened and suggesting alternatives. The checkout form preserves their information so they can try again without re-entering everything. Failed attempts are logged so you can see what is going wrong."

Red flag answer: "It just shows an error." or "The page reloads." or "I have not thought about that yet."

A developer who does not plan for failures is going to deliver an integration that breaks in production. Every payment integration must handle: card declined, insufficient funds, network timeout, bank authentication failure, and general errors. Each of these should show the customer a helpful message and a path to try again.

The only acceptable answer: "Yes, absolutely. I will build and test everything in test mode first. I will test successful payments, failed payments, webhooks, and edge cases before switching to live keys."

Red flag answer: "We can just test with small amounts in live mode." or "I will test it on my local machine."

Paystack provides a full test environment with test API keys and test card numbers. There is zero reason to skip test mode. A developer who wants to test with real money either does not know about test mode (bad sign) or is too lazy to use it (worse sign).

Ask the developer to show you a test transaction before they switch to live mode. You should see the full flow: customer pays, order updates, webhook fires, confirmation is sent. If any part of this fails in test mode, it will fail with real customers too.

Good answer: "I will disable the pay button after the first click, use a unique reference for each transaction, and check for existing transactions with the same reference before creating a new one. I will also implement idempotency so that retried requests do not create duplicate charges."

Red flag answer: "That should not happen." or a blank stare.

Double charges are a common problem with payment integrations. They happen when the customer clicks "Pay" multiple times (because the page is slow), when the webhook fires multiple times, or when the redirect and webhook both try to update the same order. A competent developer anticipates all of these scenarios.

The only right answer: "You do. You sign up for Paystack with your own email. You own the credentials. I need the API keys to build the integration, and you can add me as a team member if needed, but the account is yours."

Red flag answer: "I will set it up for you." or "I already have an account you can use."

Your Paystack account controls where your money goes. If a developer owns the account, they control your money. They can change the settlement bank account. They can see all your transactions. If you have a falling out, you might lose access to your payment system entirely.

Always sign up for Paystack yourself. If the developer needs access, add them as a team member with limited permissions through the Paystack Dashboard. Remove their access when the project is done.

Good answer: "You will receive the complete source code, documentation explaining how the integration works, all API keys and credentials, and a walkthrough of how to manage the system. I will also be available for a support period after handover to address any issues."

Red flag answer: "Just let me know if anything breaks and I will fix it." or "You do not need the code, just use the site."

You are paying for a product. You should own it completely when it is done. The code, the documentation, the hosting credentials, everything. If the developer disappears tomorrow, another developer should be able to pick up where they left off.

Get this in writing before the project starts. A simple agreement that lists the deliverables, the timeline, and the payment terms protects both you and the developer.

For more guidance on project handovers, see our guide on how long a Paystack integration takes and red flags in a developer quote.