PUBLISHED DATE: 2025-08-15 15:23:00

Publicis Sapient

CORE MODERNISATION PLAYBOOK

Modernize your core bank in four clear steps.

The Core Banking Conundrum

There are two statements upon which almost every bank leadership team will agree:

  1. Their current core technology stack is struggling to keep up with the rapid shift to the digital-first, seamless interactions their customers, colleagues, and partners expect.
  2. Replacing these technologies is risky, complex, and expensive.

However, the shift to modern core technologies is inevitable. Every year, banks are investing more time and money just to maintain the status quo. New regulations, rising digital expectations, and open banking are pushing legacy systems to their limits. Workarounds have made additional change riskier and more expensive. With increasing digital transactions and rising customer expectations for personalized interactions and connected offerings, these challenges will only intensify.

Key Statistics

The Case for Core Modernization

Replacing core systems is no easy task. Historically, proposing a core system transformation was a risky move for CEOs and CIOs, with many programs overrunning, overspending, and ultimately failing to deliver value. But times have changed. New technologies—cloud, coreless banking systems, and a surrounding ecosystem of SaaS solutions—have matured and been proven, enabling differentiated services. More progressive, iterative approaches to core modernization can significantly mitigate transformation risks.

Put simply, the time to transform is now.

Benefits of a Modern Core Banking System

A New Approach to Core Modernization

This guide lays out a new approach to a longstanding challenge. It outlines how you can modernize your current core technology stack and deliver the experiences your customers expect, while sidestepping the pitfalls that cause most modernization projects to fail.

You will:

We’ve broken down the process into four clear, actionable steps.

Your Four-Step Guide to Core Modernization

At each step, we’ll list the jobs you need to do and the pitfalls you need to avoid to deliver your modernization program without a hitch.

Step 1: Confirm Your Ambitions

A successful modernization program begins with a clear and aligned ambition—one which everyone believes in and is committed to, from the board to on-the-ground teams. Core modernization efforts fail when ambitions are poorly defined or misdirected.

Critical Mistakes to Avoid

Step-by-Step Guide

Shape the Case for Change Understand the Success Requirements Ensure Leadership Team Commitment Establish the Program Leadership Team

Step 2: Mobilize the Program

With your ambition set, you need to set up the program for success: with the right people, the right roadmap, and the right vision for what can be achieved and when. Without the right preparation, modernization programs cannot succeed.

Common Preparation Pitfalls

Step-by-Step Guide

Mobilize the Program Team Confirm the Product Roadmap Design the Coreless Architecture Fast-Track Critical Enablers

Step 3: Prove the Platform

Now it’s time to deliver. It’s critical to prove the new platform via a ‘pathfinder’ that includes a customer-facing launch. Getting to market quickly builds belief in the new capabilities and enables learning and continuous iteration through real experience. The first release is pivotal to proving the modernization program and learning for subsequent releases.

Common Pitfalls

Step-by-Step Guide

Shift into Action Deliver the Pathfinder (Re)shape the Post-Pathfinder Scaling Roadmap

Step 4: Modernize, Progressively

With the platform proven, it’s time to accelerate its expansion and transition from the legacy to the new modernized platform through a series of iterative releases. Ensuring a safe shift from legacy to modern platforms is a real challenge. It’s critical to prepare appropriately and leverage a full spectrum of levers to mitigate risks.

Additional Pitfalls

Step-by-Step Guide

Expand the Coreless Platform Scale the Modernization Factory Sustain the Change

Core Modernization FAQs

Do I really need to modernize?
Yes. Core modernization enables significant efficiencies—from automated processes to streamlined reporting—and creates new growth pathways. Within the next five years, a gulf will open up between those that have modernized and those that have not.

Is it risky to build a coreless architecture?
Significant investment in financial services technology has improved the maturity of major SaaS providers. Integration patterns are proven, and with the right engineering know-how, foundational elements (like API frameworks) can be quickly set up. The benefits now outweigh the costs.

Can you effectively mitigate the risks from migration?
It’s not easy, but it is possible. New technologies and approaches make the process easier to manage. Commitment from business and operational teams, in addition to technology teams, allows for broader levers, such as enhanced product offerings to incentivize voluntary customer migrations. New UI/UX design patterns can ensure a seamless transition for customers.

How do you handle the dual-run interim state?
Various methods support building out the new platform while running existing capabilities. Establishing a “model office” for new functionality that grows as volumes expand is useful. Understanding the future state and required changes ensures a strong transition. Being proactive—bringing in the right skills and capabilities—is critical.

What are the main reasons these programs tend to fail?
Often, there is a failure of alignment across the senior leadership team on the modernization ambition. Success requires sustained commitment and continuous releases, rather than “big bang” launches, to build belief and prove the new model. Speed and quality of delivery are essential. This approach challenges existing ways of working, so regular communication and engagement are critical to bring the organization along the journey and appropriately challenge existing approaches.

Let’s Start Your Core Modernization

While the opportunity to modernize your bank’s core may seem daunting, with the right planning and partners, you can position yourself for success. There will be challenges ahead, but staying focused on the big picture and maintaining your team’s enthusiasm will sustain you through the hard days.

Choosing the right partner is critical. Working with a partner experienced in creating modern coreless architectures helps you identify your goals and navigate the complex journey to a more efficient banking model.

Success requires:

With success, you can harness the creativity of global tech giants, enabling more automation, greater personalization, and faster release cycles to realize the full power of digital transformation.

We’re ready to help you discover the exciting possibilities of core modernization. With our experienced team, stress-tested methodologies, and unique SPEED capabilities, we’ll work with you to create banking products that put your customers first.

Our SPEED Capabilities

Contact Us

To discuss how we can help you modernize your core, please get in touch with one of our experts:

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