Software maintenance for public administration: How old systems lead to digital sovereignty

Author: Björn Groenewold | Published: 9 February 2026

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"In fifteen years we have not seen a project that could not be rescued — the question is whether the effort pays off." — Björn Groenewold, Managing Director, Groenewold IT Solutions

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The Digital Challenge Facing Municipalities

Short: Germany's Online Access Act (OZG) requires administrative services to be offered digitally.

Germany's Online Access Act (OZG) requires administrative services to be offered digitally. Many municipalities are failing to meet this requirement.

The reason is not a lack of willingness — it is outdated legacy systems. These systems form the backbone of administrative processes.

At the same time, they block the modernisation that OZG demands.

Software maintenance for public administration is not a complete system replacement. It is a strategic, incremental approach. It preserves the expertise embedded in legacy systems while making the IT infrastructure sustainable.

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Four Problems Created by Legacy Systems in Administration

Short: Many critical administrative processes — registration offices, budget management, social services — run on software from the 1980s and 1990s.

Many critical administrative processes — registration offices, budget management, social services — run on software from the 1980s and 1990s. These systems create four concrete problems:

1. High Maintenance Costs

Maintaining COBOL and PL/I systems requires specialists who are expensive and scarce. The cost per change request is high. The risk of introducing errors is also high.

2. Security Vulnerabilities

Older architectures receive no security updates. They are vulnerable to modern cyberattacks. GDPR compliance becomes extremely difficult without current software.

3. Poor Interoperability

Legacy systems are often monolithic. They cannot communicate with modern APIs. Connecting administrative services across federal and state levels requires expensive workarounds.

4. Operational Risk

A critical system failure can paralyze an entire administration. Citizens cannot access services. Staff cannot perform their work. Recovery takes days, not hours.

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Why OZG Digitalisation Fails Without Backend Modernisation

Short: The OZG requires more than online forms.

The OZG requires more than online forms. It requires the underlying processes to be digitalized too.

When a modern digital frontend connects to an outdated, inefficient backend, the result is a slow and error-prone system. Citizens experience this as poor service, even though the frontend looks modern.

IT modernisation in municipalities is the necessary foundation for meeting OZG objectives. It is not optional.

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The Software Rescue Approach for Public Administration

Short: A structured rescue programme uses proven techniques to modernise without replacing:

A structured rescue programme uses proven techniques to modernise without replacing:

• Security patching: Critical vulnerabilities are closed immediately without touching the core system
• API wrappers: Modern interfaces are placed in front of legacy systems, enabling digital services without backend replacement
• Strangler pattern migration: New modules replace legacy functions piece by piece, over a defined timeline
• Documentation: Undocumented legacy code is analysed and documented, reducing dependency on individual specialists

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The Path to Digital Sovereignty

Short: Digital sovereignty means that a municipality controls its own IT.

Digital sovereignty means that a municipality controls its own IT. It is not dependent on a single vendor or a single specialist who knows the system.

Software rescue creates this independence step by step.

The goal is a documented, maintainable, and secure IT infrastructure — one that meets OZG requirements and can evolve.

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References and Further Reading

• Bitkom — German digital industry association
• German Federal Office for Information Security (BSI)
• European Commission — Digital strategy

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About the Author: Björn Groenewold (Dipl.-Inf.) is Managing Director of Groenewold IT Solutions GmbH. Since 2012, he has supported over 250 projects — from legacy modernization to AI integration.