The Person Who Knows How It Works Leaves in Six Weeks

The announcement is friendly. After eleven years, the engineer who built the billing integrations is retiring at the end of next month. Then your manager adds a line meant for you. You will be taking over their area, so please spend as much time with them as you can.

Six weeks. Eleven years. The usual plan is to ask them to write everything down, and it is the plan most likely to fail.

People who know a system deeply struggle to write down what they know, because most of it never feels like knowledge to them. It feels like the obvious next step. Ask for documentation and you will get a careful description of what the code does, which you could have read yourself, and very little of the judgement around it.

Learn by watching real work instead. Sit in on everything they touch for the first two weeks. Every support question, every odd failure, every call with the finance team. Ask them to narrate as they go. Why did you look there first? How did you know that was not a real error? What would worry you here?

Then swap seats. For the next two weeks you do the work and they watch. This is where most of the learning happens, because your mistakes show them what they forgot to tell you. Their small wince when you reach for the wrong log file is worth a page of documentation.

Keep three lists as you go. The questions only they could answer. The things they would never do, and why, because those warnings are often the most valuable knowledge in the building. And the people they call when something breaks, with what each one is good for. Ask for an introduction to every name on that last list while an introduction from them still means something.

Use the final fortnight as a dress rehearsal. Handle everything yourself and save your questions for the end of each day. Whatever you still cannot do alone is the honest gap, and you have found it while you can still ask.

Finally, ask whether you may contact them after they leave, once or twice, for the truly strange cases. Most people say yes, and are quietly glad to be asked.

– Asael Shinder