This essay is an extended version of a talk I gave at Paperless Post about coffee and customer happiness. While the talk was originally titled “Coffee and the Art of Software Maintenance”, I figured that customer happiness is overall a much more fitting for the topic.
Two years ago, I wrote about the virtues of monitoring. A lot has changed, a lot has improved, and I’ve certainly learned a lot since I wrote that initial overview on monitoring as a whole.
The need to measure everything that moves in a distributed system or even simple web apps is becoming the basis for thorough monitoring of an application.
When I built the billing process for Travis CI’s commercial offering, I decided to try out some new things to avoid callbacks in ActiveRecord models, including validations.