Fifteen years ago, banking technology had a problem.

Most financial institutions were running on systems that were rigid, tightly coupled, and painfully slow to change. Launching a new financial product felt like a multi-year odyssey. Teams wrestled with monolithic legacy systems, navigated layers of hard-coded logic, and hoped that changing one feature wouldn’t break everything else.

We looked at that reality and decided there had to be a better way. Building a slightly improved version of the old model wasn’t enough. The model itself needed to change.

So we pioneered composable banking.

Seeing the gap before it had a name

Back then, “composable banking” wasn’t a buzzword on industry category. It was simply an observation: banking systems shouldn’t be monoliths. They should be flexible and able to evolve over time.

Instead of one system trying to do everything, why not build a core that does what it does best and connect it to other specialised services through APIs?

That thinking shaped how Mambu was built from day one: cloud-native, API-first and designed to work as part of a broader ecosystem. Not as a replacement for everything, but as a foundation you can build on.

From the start, Mambu was built as a true SaaS, composable architecture that is now essential to the global financial services landscape. While others are busy "cloud-washing" their old technology to fit the new narrative, we are operating on a single, evergreen codebase.

This means every Mambu customer, from a nimble fintech in Brazil to a Tier 1 bank in the UK, runs on the exact same, most up-to-date version of our platform. No disruptive upgrades. No technical debt dragging you down.

So, what is composable banking?

At its simplest, composable banking is about choice, freedom and adaptability.

Rather than relying on a single, all-in-one core banking system, institutions can assemble technology stacks from independent components, each chosen for a specific purpose. These components communicate through APIs and can be added, removed, or upgraded without overhauling the entire system.

Think of legacy banking systems like a pre-built, glued-together castle. It looks impressive, but if you want to move a window or add a tower, you have to smash through a wall.

Composable banking is different. It is like a set of building blocks.

Moving away from one-size-fits-all banking

Traditional core systems are often deeply intertwined. Changing one thing can affect everything else. That’s why even small updates can feel high-risk and high-effort.

Composable banking flips that model.

New capabilities can be introduced without disrupting what already works. Existing systems don’t need to be ripped out, they can run in parallel with a composable platform like Mambu and gradually migrate without interrupting day-to-day operations.

This is what makes composable particularly powerful: it enables modernisation without forcing a “big bang” transformation.