On the game show Who Wants to Be a Millionaire?, when a contestant is one question away from winning everything and needs that one last shot to stay in the game, they reach for a lifeline. They could ask the audience, go 50:50, or phone a friend.

For many business owners, that moment occurs more frequently than TV cameras ever capture. Inventory is waiting, a big opportunity arises just before payments clear, cash flow is uncertain.

So when the call comes to us at Moniepoint, “We’ll spot you,” we say. “Keep your business running.”

The call

The call to build a lifeline for businesses began with what every Moniepoint build starts with: data.

The loans team pulled anonymised transaction data, credit utilisation patterns, and repayment behaviour to identify who would actually benefit. The customer profiles that emerged were real people with real business rhythms. They needed flexibility, not long-term debt. 

For them, overdraft was a bridge, a few days of coverage that kept their operations moving without disrupting cash flow. A credit line tied directly to their account, allowing them to go into negative up to an approved limit, where they pay interest only on what they use. The repayment cycle would be structured with precision. Each time the account went negative, a 30-day clock started. Once the account returned to a positive balance, the cycle reset. No penalties for paying early. No unnecessary friction.

Christian, our PM on the subject, explains it like this: “Businesses use what they need, and when things pick up again, they clear it.”

That call would set off months of prioritisation, testing, rebuilding, and refining. 

The build

We didn’t build from scratch because we didn't need to. We repurposed the existing working capital loan (WCL) infrastructure: the same rails that power lending for millions of businesses across Nigeria.

The idea was to stand on a proven foundation while introducing flexibility. But while the WCL system worked in a linear way (loan → disbursement → repayment), overdraft had to work cyclically, i.e customers dipping in and out of negative balances multiple times within a contract period. That required a different logic flow and more dynamic data handling.

Initially, we layered overdraft on top of the WCL stack, sharing components such as user eligibility checks and credit scoring; however, we gradually decoupled it until it became a fully independent service.

One major consideration during the build was redundancy, as multiple credit products (loan, overdraft, and future ones) shared similar but not identical request flows. Instead of building each component separately, the team utilised a microservices architecture, which enabled each component to be integrated into different credit products without requiring code rewriting.

Overdraft approval isn’t just a one-time event. It’s a living credit decision that depends on how the customer behaves over time. The backend continuously pulls signals from multiple data points:

• Transaction volume and frequency

• Inflow-to-outflow ratios

• Average balance levels

• Historical repayment behaviour

• Business seasonality patterns

These signals feed into a risk model that updates the customer’s credit profile in real-time. If a business consistently manages its overdraft responsibly, its overdraft limit can be automatically increased. If anomalies appear, the system tightens access.

I call it data-driven empathy: we let the data guide us on when to trust more and when to pull back gently.

The product

Unlike a loan, an overdraft doesn’t disburse funds upfront. It allows the account balance to go below zero, up to a credit limit, while continuously recalculating usage and interest. When broken down, it looks like this:

• Dynamic negative balance tracking: The system continuously reconciles all debits and credits to determine how far below zero a business has gone.

• Interest engine: Calculates interest only on the amount used and only for the duration it remains outstanding. If a user clears the overdraft early, interest stops accruing immediately.

• Payback period: Each time the account dips into a negative balance, a repayment timer starts. When the customer repays, the timer resets. This keeps repayment fair and transparent.

• Renewal flow: The current contract spans 6 months, allowing users to enter and exit overdrafts repeatedly during that period.

From a systems view, this required building non-linear credit accounting, one of the most challenging things to engineer in lending technology, because it breaks the traditional “loan ledger” model.

From the user’s view, overdraft looks deceptively simple; just a balance that can dip below zero. But making that invisible experience required precision. The team integrated overdraft natively into the Moniepoint business banking app.

For the mobile release, the execution synced backend calculations (interest, clock reset, repayment rules) with frontend UX updates in real-time. This required near-flawless event handling, the kind that demands overnight testing and deep collaboration between the product and engineering teams.

The technical sophistication of overdraft, for me, is Moniepoint’s engineering culture.

• Every build underwent thorough internal reviews: not just “does it work?” but also “is this the best possible way to make it work?”

• The team drew on knowledge from our “day ones” who’d built our earlier credit systems, ensuring that nothing was reinvented.

• During the mobile release, engineers worked around the clock to validate repayment logic, simulate thousands of credit scenarios, and debug to eliminate edge cases.

That grit and technical depth, core values for us at Moniepoint, ensure we never chase shiny features; we engineer reliability.

The lifeline

It’s easy to romanticise credit as a growth engine, but for most small business owners, it’s survival. By the time overdraft launched as a fully independent product, we had built something capable of serving a core business need with minimal rework. It was scalable, modular, and intelligent.

The beauty of overdraft isn’t in the interface, though it’s elegant, or in the credit model, though it’s robust. It’s in how seamlessly it fits into a merchant’s day. There’s no separate login, no paperwork, no friction. It’s simply there when they need it, invisible until the moment it matters.

That invisibility is the ultimate sign of mastery. The less a user thinks about a product while using it, the better we’ve done our job.

For Christian, it felt personal. “We built something that helps people catch their breath,” he said. You can measure success in uptake, repayment rates, or transaction volume, and we do, but there’s another metric that’s harder to quantify: financial happiness. 

That’s what overdraft delivers.