Playbook
Modernise your core without the disruption
Legacy core banking systems are slowing product launches, inflating costs and creating technical debt that compounds with every passing year. Mambu's composable, cloud-native banking platform gives you a practical, phased path to core modernisation, without putting your operations at risk.
We developed this playbook to give you a clear guide on how to modernise your core systems at your own pace while minimising risks and maximising value.
Modernise your core, your way.
Replacing legacy banking infrastructure is one of the most complex undertakings a financial institution can face. But doing nothing carries its own risks. Rigid, monolithic systems make it harder to launch new products, respond to regulatory change and compete with digital-native challengers.
Composable core banking takes a different approach. Rather than a disruptive, all-or-nothing system replacement, it lets you migrate in phases, product by product, geography by geography, while keeping your existing operations running smoothly. You choose a strategy that fits your business, your customers and your appetite for change.
The result is a modern banking infrastructure that is API-first, cloud-native and built for rapid scalability, without the operational chaos of a complete overnight switch.
Five proven ways to migrate from legacy systems
Greenfield build
Starting from scratch with a clean slate and fresh technology. Best suited for new institutions and neo-banks entering the market for the first time with no legacy constraints.
Dual core - shared legacy
Launching a new fintech sponsored by an existing bank, using current technology and integrations. Ideal for fast market entry, though core is still tied to the sponsor bank.
Dual core - on the edge
Run a new composable core alongside your existing legacy system. Share legacy functions where needed while differentiating with modern capabilities at the edge. This is a lower-risk, phased approach suited to institutions that want to modernise incrementally.
Speedboat spin-off
Create a legally and operationally independent entity, funded by the parent organisation, to capture new market segments fast. The parent retains shared ownership while the spin-off moves at a different pace and with greater agility.
Full legacy replacement
A complete migration from your existing core to a modern platform. The highest complexity model, but with rigorous planning, phased execution and continuous executive governance, it delivers a clean, future-ready foundation.
Core transformation
Hear from our customers
“We needed a solution native to that environment which shared the lean and agile attributes of our business. Mambu offers us scalability, flexibility and speed to market at a fraction of the cost of traditional core systems.”
Co-Founder & CTO, New10
“We’ve seen a lot of changes in the industry, so this end-of-life warning was simply the latest. Replacing the core banking system gave us the chance to modernise to meet current needs and set ourselves and our customers up for the future.”
Chad Griffin, CEO, League Data
When the bank decided to modernise its core banking system, they selected Mambu's cloud-native banking platform because it offered infinite scalability and quick time to market.
GoTyme
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