- Maintenance
Your WinDev developer retires in three months
It is the most frequent and worst-handled situation. What to do while they are still there, and the mistake that costs the most.
· 4 min read · AzerOps
A business application has been running for fifteen years. One person knows it. They leave in three months. This situation occurs every week in French companies, and how it is handled determines the cost of the next five years.
The most expensive mistake
Waiting for the procurement process to finish before starting.
The natural reflex is to consult providers, compare, negotiate, sign, then start. That path takes two to four months in a mid-market company. By the time it completes, the person has gone, and the selected provider has to reconstruct everything by reverse engineering.
Two weeks paired with the historical developer are worth three months of reverse engineering after their departure. It is the only case where we recommend starting a short assignment before contract negotiation ends, treating it as a one-off engagement if necessary.
What to capture, in order
The unwritten business rules. Why this calculation has an exception for contracts before 2015. Why this report excludes that category. That knowledge exists only in one head and cannot be inferred from the code: the code says what is done, not why.
Operating procedures. What to do when the nightly job fails. Who to call at the vendor. Where the licences are. What the service account password is, and where it is stored.
The integration map. Which files are dropped by which systems, at what time, in what format. It is these undocumented dependencies that break first.
The known traps. "Never re-run this job twice." "This field must stay at zero or the month-end report is wrong." Every old application has about ten of them, and each one costs an incident if discovered through use.
The method that works
Do not ask the person to write the documentation. That is what they are always asked, they do not have time, and the result is a list of things obvious to them.
Instead, have an outsider work beside them, asking naive questions and writing. Documentation produced by a third party discovering the application is usable by another third party; documentation produced by the expert is not, because it omits everything that seems obvious to them.
The deliverable to require
A takeover note usable by a third party, validated by a simple test: give it to a developer who has never seen the application and ask them to implement a minor change. If they succeed without calling anyone, the note is good.
And afterwards
Train two people, not one. Recreating a single-person dependency with a provider instead of an employee does not solve the problem, it relocates it. The clause to have written into the maintenance contract is simple: two named contacts, familiar with the file, with an obligation to notify any change.