There’s no one size fits all in application modernisation. A spectrum of options ranges from lift-and-shift (moving unchanged applications to the cloud) to rebuilding from scratch or replacing with SaaS or off-the-shelf products. In the middle, refactoring offers a way to prioritise and implement changes over time.

Lift-and-shift can seem attractive: no code changes required, reduced costs from running in the cloud. But the downsides are significant:

• With no underlying changes, companies won’t see improved process performance.
• Without using technologies like analytics and ML, there’s little opportunity to innovate or implement continuous improvement programmes.
• Eventually, a more extensive modernisation programme will be needed, negating ROI generated from rehosting.

Replacing or rebuilding represent high costs and risks. Replacement may be a viable option – although customisation increases costs and timescales. Rebuilding offers a good opportunity to create optimum functionality and performance but could take years to complete. Both options require existing applications to be maintained until the new system is deployed.

Refactoring is less risky and more agile. With a good understanding of the requirements, a transformation strategy and roadmap can be devised, focusing on priority areas. Approaches such as robotic process automation (RPA) or adding an API layer can enable quick wins and minimise disruption to other apps. Advantages include distributing costs over the programme lifetime, achieving ROI faster, and pivoting if better solutions emerge. However, a full refactoring transformation takes time.