Migrate legacy applications to new languages with AI

Teams migrate legacy applications to new frameworks and programming languages, such as COBOL to Java

Needs setupAI Act: no extra obligationsCreating software & codeDigital & tech, Banking & finance, Insurance

Fits: IT & software development

Code from COBOL or old frameworks is converted to a modern language faster, and comparison tests show whether the new version calculates exactly like the old one. You become less dependent on a few experts in the old language.

Is this for you?

  • You run applications in COBOL, old Java versions or frameworks that are being phased out, for which there are hardly any experts left.
  • You can run the old application with test data and record its results so you can check the new version against them.
  • There are still people who know the business logic of the old application and can assess deviations.
First step today

Take a short, non-critical piece of code from the old application, remove company names and credentials, and have it converted with the template below. Work out three test cases with rounding and limit values by hand according to the rules of the old language and compare them with the result of the new version.

How to go about it

  1. Define scope, target language and standard of equivalence
  2. Provide old code, test data and a comparison environment
  3. Have the code converted module by module
  4. Have the old and new versions compared
  5. Put the new version into operation step by step
  6. Document what has changed

Templates to copy

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Included in the training

The complete guide

  • 6 steps explaining exactly what to do
  • 3 proven templates to copy into your own AI
  • Safe use: data, checking, deciding, informing
  • Pitfalls, effort and how to recognise success

With the training you get all 430 guides for as long as your access runs.

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Same approach, other use cases

13 more use cases follow the pattern “Creating software & code”.

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G-DT-05 · Legal status 08.10.2026