Legacy technology: The good, the bad, and the toxic

Part 3 of a series on toxic technology. In part 1 I introduced toxic technology, and part 2 explained the symptoms.

The term ‘legacy’ when applied to technology has a dual meaning. Some define legacy technology by emphasising its risk. They use the term to refer to technology which, through an ageing process, has become outdated and hard to change. Legacy technology has become toxic over time, by accumulating risk.

Others emphasise the value in legacy technology such as the Legacy Code Rocks and Festival of Maintenance communities. They celebrate the usefulness, beauty and lessons to be learnt from past technology. This perspective is also a call-to-action – saying there should be more focus and celebration of maintenance.

Both these perspectives are needed. Legacy technology has both risk and value. Legacy remains a useful term for describing the technology inherited by organisations – combining the good, the bad, and the toxic.

Despite a dual meaning, the term legacy is used negatively, more often than positively. In common usage, it is becoming a synonym for toxic technology – creating a sense that anything old is bad. Allowing legacy to become a synonym for toxicity is dangerous. It creates an unhealthy divide where new is good, and old is bad. When old is bad, this devalues the important role of maintenance and continuous improvement. When old is bad, it creates generational divides based on engineers’ familiarity of technology. When old is bad, organisations fail to learn the skills to sustain technology over decades – they become trapped in cycles of delivery booms, and toxic legacy busts.

Organisations need to be clear in their intent, and strategy around complex areas like legacy technology. Because the term legacy is both positive and negative, it is hard to communicate intent. Legacy might need modernising, migrating, decommissioning or maintaining – but its hard to summarise what should be done in general. The idea of toxic technology, and toxic characteristics, is easier to use – it’s unambiguously negative. Toxicity must be minimised. If toxicity is growing, something must be changed. If toxicity is reducing, the strategy is working. If a new system is created, and it’s already full of security vulnerabilities and accessibility issues, then it is toxic. If a legacy system has been patched, upgraded, modernised and is keeping pace with changing user needs, it is not toxic. It doesn’t matter how much legacy an organisation has, it matters how toxic this legacy is.

The volume of toxic legacy, for many organisations, is a problem decades in the making — it cannot be solved quickly, or cheaply. The systemic causes of toxic technology have not been addressed, so next generation’s toxic legacy is still being created today. It will take bold leadership to challenge these causes which lie, often hidden, in our current ways of working – in finance, procurement, design and technology delivery.

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  1. Again, a brilliant article. “ systemic causes of toxic technology ” – probably warrants more coverage. What a user wants, what a user needs, what the business collectively thinks a user needs, what the technology teams thinks a user needs, and what the user really gets – all of these should be the same, but it is rarely so! For a fact, this requires bold leadership. No doubts.


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