Hardening payments for a vehicle-finance platform
Took a lending platform off a single server, wired up its payment and accounting integrations, then ran a security review nobody had asked for, which turned up 52 findings.
The problem
A South African vehicle-finance platform ran on a single EC2 instance with no redundancy, and its payments flowed through integrations that nobody had looked at closely in a while. When customers’ money is involved, both of those are serious risks.
What I did
- Led a team of three engineers in migrating the platform from single-instance EC2 to AWS ECS (Fargate), removing the single point of failure, and standardised CI/CD across UAT and production.
- Built the Paystack payment proxy and the Sage Intacct invoice sync, so payments and contracts land in one system of record instead of being reconciled by hand.
- Ran a full payment security review of the platform, which raised 52 findings, including critical Paystack reconciliation gaps. I then drove a structured remediation programme through to production.
How I showed up
The security review wasn’t in the brief. While working on the payment integrations I saw enough to be worried, so I raised it, scoped it and did it. A long list of findings is only useful if it gets fixed, so I prioritised them with the client and saw each one through to production.
Outcome
The platform now scales horizontally instead of falling over, payments reconcile into accounting automatically, and the critical reconciliation gaps are closed.