AI case study

APIS ITLegacy system modernization

Undocumented 1990s systems made upgrades risky. AI reverse-engineered decades of legacy code to map architectures and build modern APIs.

Published|1 month ago

Key results

Documentation Accuracy
100%
Dependency Reduction
50%
Codebase Reduction
30%

Result highlights

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The story

Context

Croatia's leading public ICT provider manages a broad set of mission-critical government systems burdened by decades of technical debt, including early-1990s mainframe jobs and 20-year-old legacy applications.

Challenge

Foundational workloads had little to no documentation and relied entirely on institutional knowledge, making it difficult to understand architectures...

Solution
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Scope & timeline

  • 10x faster architecture documentation and process analysis
  • API manager upgrade time cut from weeks to 5-6 hours
  • 5-6x productivity gain in test automation delivery vs LLMs
  • Test automation platform delivered in 2 days

The company

APIS IT logo

APIS IT

apis-it.hr

Central government IT agency for public administration systems and digital services.

IndustryGovernment & Public Sector
LocationZagreb, Croatia
Employees251-1K
Founded1964

The vendor

Enterprise technology and consulting for cloud computing, AI, and business solutions.

IndustryTechnology
LocationArmonk, New York, United States
Employees100K+
Founded1911

Use case

APIS IT's Legacy system modernization is part of this use case:

Code Generation
129 case studies(+93% YoY)
Proven impact?
LowModerateVery Strong
4.3Moderate
4.2Moderatewithin Product Engineering

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