ausum

Legacycode

In more than 20 years we have watched technologies, languages and frameworks come and go. All that time we have been working on legacy systems – and we even built some of them ourselves.

01 · Challenge

systems that work, but…

If you find yourself nodding while reading the points, we will come, assess the situation and help you before it becomes a serious problem.

/01

Missing documentation

Documentation was lost, corrupted or marked as not needed during the last overhaul of the document management system. It sits on an unreadable medium or a failed hard drive, or was simply lost, forgotten, never delivered.

/02

Loss of key people and know-how

Remember Joe? The one who left last year after being with the company forever. Nobody really knew what his duties were, and the handover was done in a hurry. Yes, that one – the one who knew what the system does and why it was declared critical. And yes, he is gone and not coming back.

/03

Technical debt and outdated platforms

If your platform is older than your interns, half of its software frameworks can no longer be downloaded, error messages are only discussed on obscure Chinese servers and Google returns just five results, it may already be too late.

/04

Security and operational risks

Oh, your hardware is out of production and out of support? But you can’t replace it, because the software needs an old operating system that is incompatible with new hardware. Plus, the list of known vulnerabilities for those old systems is longer than the list of their features. But don’t worry – if you’re lucky, the hacker will be too young to know how to connect to the good old systems.

02 · Services

from ambiguity to clarity

We use the vast experience gained over decades in the field to see what you cannot. Our work is mission-oriented and deliberate with clear outcomes.

S.01

Source code analysis

We read, understand and organise your source code, and identify its key parts, dependencies and quality.

S.02

Reverse engineering and documentation

We create, update or complete the documentation so that work on the system can continue.

S.03

Architecture and dependency mapping

We bring order and structure, mapping the system architecture with its individual building blocks and their relationships. We describe its inner workings as well as its interfaces to the outside world.

S.04

Risk and security assessment

We identify and assess both general and security risks of the system, and propose solutions or mitigations together with a clear implementation plan.

S.05

Modernisation and migration strategy

We identify the key parts of the system and prepare the approach to modernisation and its delivery, covering every level – from technical through project and financial planning to the implementation itself.

S.06

System takeover and operational continuity

Leave it to us – we analyse your system and take it over into our care with minimal impact on your operations.

03 · How we work

clarity, control, continuity

We consult you on every step and prepare it so that we always act in line with your goals and expectations.

  1. 01

    Definition

    Understanding and clearly defining the problem and expectations is essential to reaching the goal and your satisfaction.

  2. 02

    Analysis

    Knowing where we are and what we are facing is essential to deciding where to go next.

  3. 03

    Plan

    Knowing where we are going and how we will get there is essential so that we don’t get lost along the way.

  4. 04

    Delivery

    Movement and delivery are essential so that we don’t stand still.

  5. 05

    Evaluation

    The art of looking back and seeing objectively what we have overcome is essential so that we don’t repeat the same mistakes next time.

04 · Projects

selected legacy projects

From a nationwide system in round-the-clock operation, through a database with twenty years of history, to modernising a Visual Basic 6 application. Four examples of how we helped clients regain control of critical systems.

Healthcare · Critical infrastructure
24/7/365availability of a nationwide system
Long-term maintenance and development

Seamless, secure and scalable nationwide healthcare operations

Developed since 2010 and in operation since 2016/2018, the system is used nationwide by tens of thousands of users and stores hundreds of millions of records. Since 2018 our team has been solely responsible for its maintenance and upgrades – including several rounds of performance and functional upgrades, all under 24/7/365 availability.

2018+sole responsibility
100M+records
~25 %of code by the original team

Our role

  • Code maintenance and upgrades (C#)
  • Test and integration maintenance
  • Requirements and dependency analysis
  • Full development life cycle
  • Secure development per ISO 27000
Project detailsClose
Seamless, secure and scalable nationwide healthcare operations

It is a large-scale system with many integrations and, as part of critical infrastructure, faces severe security and performance requirements. Although several members of our team were part of the original development team, they produced only around 25% of the code we maintain – the rest we had to take over, understand and keep running.

We maintain hundreds of complex test scenarios integrated with third-party modules and run the full secure development cycle, including audits, static analysis and vulnerability monitoring.

Databases · Current-state analysis
3foreign keys across hundreds of tables
Deep-dive analysis

Uncovering complexity, delivering clarity: a deep dive into a legacy database overhaul

One database, eight years since its last major upgrade, terabytes of data, hundreds of tables, thousands of stored procedures – and three foreign keys. Constant performance issues, no control over data consistency and more than 20 years of development.

20+years of development
1000+stored procedures
1000+relationships uncovered

Our role

  • Current-state analysis
  • Recommendations
  • Domain model from existing data
  • Performance upgrades
Project detailsClose
Uncovering complexity, delivering clarity: a deep dive into a legacy database overhaul

We combined automated and manual analysis and built custom tooling to automate the analytical process. We found three solutions, developed over 20+ years, coexisting inside the database and intertwined into one.

We identified relationships between tables, built the application's domain model, found unused parts and mapped table usage across stored procedures and functions – several thousand relationships and dozens of primary keys in total.

Result: the cost of a complete overhaul was judged too high, and the findings became the argument for an entirely new implementation of the system.

Healthcare · Czech Republic
20–30year-old core systems
Strategy and architecture

Transforming legacy systems: a strategic roadmap for digital evolution in healthcare

The digital transformation of the second-largest hospital in Czechia had stalled – insufficient funding, resistance to change, vendor lock-in and a devastating cyber-attack. The result: core systems 20–30 years old, still running MS-DOS-style text interfaces in 2023.

ESBcore of the gradual transition
4transition steps
EUfunding support

Our role

  • IS ecosystem map
  • Transition strategy
  • Information systems architecture
  • Transition project plan
Project detailsClose
Transforming legacy systems: a strategic roadmap for digital evolution in healthcare

We mapped the information system ecosystem and classified systems by importance and age – most were out of support, with severe vendor lock-in. We then assessed alternatives within the customer's budget constraints while balancing pressures from several factions in the hospital's C-suite.

Gradual transition strategy

  1. Upgrade the existing Enterprise Service Bus
  2. Central electronic health record storage as part of the ESB
  3. Connect every module to the new ESB and copy every record transmitted from legacy systems
  4. Use the central storage as the source for newly implemented interfaces

This lets the customer spread the transition over time without severely affecting day-to-day operations or the friction of a big-bang approach. We also helped prepare proposals to secure funding from EU structural funds.

Aviation · Application modernisation
VB6 → .NET20 years of development, a new generation
Turnkey modernisation

Rebuilding the past for the future: modernising aviation services

The system the customer uses to serve its clients had been developed for 20 years in Visual Basic 6 – with COM objects, Windows services, web services and many third-party integrations. The goal: a new version with as few functional changes as possible, on current technology, with significantly shorter testing and deployment times.

3 mo.to milestone I delivered
100 %containerised
CI/CDautomated deployment

Our role

  • Full development life cycle
  • DevOps
  • Project management
Project detailsClose
Rebuilding the past for the future: modernising aviation services

We opted for a microservices architecture with a .NET backend and a React frontend, with automated UI and unit testing. The application is fully dockerised and deployed automatically through pipelines.

Within three months we set up environments with automated build and deployment, completed the analysis for the first part of the application and met the milestone I targets – with the full backend stack and automatically generated parts of the solution.

05 · Technologies

platforms we understand

What we bring is, above all, experience and honest work gained over years of working on systems both small and large. In the age of AI, listing the platforms we understand is pointless – so even if you don’t see your language or platform in the list, it doesn’t mean our experienced team can’t help you.

Languages

C# / .NET FrameworkC / C++PL/SQLPHPVisual Basic 6 / COM

Platforms and databases

OracleMS SQL ServerMySQLPostgreSQLOracle Forms

Integration and architecture

SOAP / WS-*ESBBatchMonolithsMicroservicesDockerKubernetes
06 · Why ausum

a partner for good times and hard times

Our main goal is always to achieve your goals. We draw on our extensive experience to find a way even where others cannot see one.

01

Experience with critical systems

Small, large, critical – we have worked, and still work, on systems of every size.

02

An independent view

Because we come from the outside, we are not limited by habits, practices or the status quo. We look at every challenge as unbiased observers.

03

Architecture and delivery

We provide services across all phases and levels of project planning and delivery.

04

Clear, usable outputs

We say and describe things as they are – not as they seem, or as someone would like them to be.

“To improve is to change; to be perfect is to change often.”
Winston S. Churchill
07 · FAQ

questions and answers

How long does a legacy system analysis take?

It depends on the complexity of the system and the goal of our work. For smaller systems we expect somewhere between three and six months.

Do we need to provide access to the source code?

If we are to propose changes to it, definitely. If you don’t have it but have the right to use and modify it, we will try to recreate it through decompilation.

What if there is no documentation at all?

We will design its structure and fill it in.

Can you take over or modernise the system after the analysis?

We can cover any activity across the planning, delivery and operation of systems, including taking the system over into our care.

08 · Contact

let’s start together

Let’s take the first step together – write to us or give us a call.

E-mailinfo@ausum.sk Phone+421 948 566 543
AddressKopčianska 10, 851 01 Bratislava