Modernize your legacy systems — without betting the company
Incremental modernization with the strangler fig pattern. Each module migrates, validates, and goes live without breaking what works. No big-bang risk.
Free, with a senior consultant. The plan is yours even if you don't hire us.
The system nobody wants to touch
Your legacy system keeps the business running, but every year it gets more expensive and riskier to maintain.
- Unsupported or hard-to-maintain technology
- Dependence on a handful of people who know the system
- Small changes take weeks
- Fear of a big-bang migration that stops operations
Incremental modernization
With the strangler fig pattern, the new system grows around the old one until it replaces it, module by module.
Assessment of the current system
We learn what the system does, which business rules it holds, and what depends on it.
Module-by-module migration
Each module migrates, validates, and goes live without breaking what works.
Zero-downtime cutover
Operations keep running while the system is modernized.
Cloud migration when it makes sense
We move the modernized system to the infrastructure that fits you best.
COBOL and AS/400 modernization
Many US enterprises still run core operations on COBOL and AS/400. We modernize them incrementally, preserving the business rules they hold, without a big-bang cutover.
Stack and technologies
What we DON'T do
- We don't do big-bang migrations
- We don't put a module into production without validating it
Frequently asked questions
Why Four Sides Group
ISO 9001:2015 certified process
Pay only after validating each stage.
Source code 100% yours
No recurring licenses, no vendor lock-in.
Enterprise architecture from day one
Public/private environments and server management included.
+14 years of continuous production
Our oldest system has run without interruption since December 2011.
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Enterprise software built around your real processes — not the other way around.
The team that built your system keeps it running, with contractual response times and monthly updates.
We connect ERPs, CRMs, custom apps and third-party APIs that didn't talk before.