Debugging microservices is a tedious task. A lot of components interact with each others and when a bug pops up identifying its root cause is complex. It gets even messier at scale.

It is difficult, but not impossible. Here, we will see how we can leverage a functional programming data type, namely Kleisli, to achieve such result.

The problem

Let’s consider the following architecture composed of four services: A, B, C and D.