Replatforming of critical and legacy systems

It works. Changing it is risky.

The system still supports important processes. Understanding what it costs to keep it running, what it really does, and how to change it without losing what matters can become increasingly difficult.

Let’s talk about your system

When a system that works becomes hard to manage.

What does continuing like this cost?

Changes need more checks. Maintenance absorbs time and skills that are hard to replace.

Do we still know everything it does?

Some rules survive in the code or in a few people’s memory. Some functions may no longer be used.

Decades of archives do not move without consequences.

Historical data, integrations, and accumulated behaviours can make a migration long and expensive.

What if it stopped tomorrow?

Where support, spare parts, or recovery procedures are inadequate, a failure can cause prolonged outages. The risk must be verified on the real system.

The complexity remains. Now we can read it.

We relate code, data, documentation, interviews, and observed behaviour. Specialist AI agents can speed up cross-checking information; our specialists verify conclusions and flag what remains uncertain.

Illustrative example

Application function

Context

Code

✓ Selected

Data structure

Technical finding

Documentation

? Information unavailable

Interview

△ Testimony to verify

Code

Origin

Code in the illustrative example.

Links the application function to a technical source.

Verification level

Technical finding, to be interpreted in context.

✓ Technical finding
△ Testimony to verify
? Information unavailable

A relationship becomes useful when we know where it comes from and what we still need to verify.

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Changing everything is not always the answer.

With more reliable knowledge we can assess whether to migrate, refactor, integrate, or limit the intervention. Sometimes the choice is to dig deeper before proceeding. When the project requires it, Shift42 can also contribute to design and delivery, alongside client teams or specialised partners.

Implementation is not automatically part of the assessment; the perimeter is agreed with the client.

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What is stopping you from deciding how to intervene?

Tell us about the problem. You do not need to have chosen a solution yet.

Let’s talk about your system

Do not send credentials, source code, or confidential documents in the form.