Author: Maik Seyfert

When you visit the East Gardens of the Imperial Palace in Tokyo Japan, you’ll either get a card and can enter the park or get told that the park is full. There is a certain amount of cards available on the entrance and each person that enters the park get exactly one. If all cards are handed out, you have to wait until someone leaves the park and returns their card. That card is called a Kanban. Kanban is a japanese word that translates to sign or singboard. Kanban is not only a signal card or token in japanese parks. According to Wikipedia it is also „a scheduling system for lean manufacturing and just-in-time manufacturing (JIT)“ developed at Toyota by Taiichi Ohno. Here also the …

What is Kanban? Read more »

Write a test that covers a use case or some functionality, then let the test run and fail. Once this is accomplished write as little code as possible so that the test passes. After the test passes turn the code into clean code; meaning refactor, simplify, adhere to convetions, etc. Done? …repeat that cycle. That approach is called Test Driven Development (TDD) according to Kent Beck. But why are we doing that?

Most of you know the situation when we had planned some work, let’s say a few different tasks. Then we started most of them, work in parallel and when time is up only a small portion of the work is really completed. In teams working towards deadlines or iterations this usually at least feels bad or has consequences, such as more budget needs to be requested or delay of delivery.

Little’s law is a theorem in queueing theory by John Little. What it says is that long-term the average number (L) of customers in a stable system equals the long-term average effective arrival rate (λ) multiplied by the average time (W) that a customer spends in the system. As a mathematical formula it’s: L = λ W In simple words, there is a relationship between the average number of customers in a stable system, their arrival rate, and the average time in the system.

Product Owner vs Project Manager, what’s the difference? Seems there is none, as many orgnizations just rename roles from one to the other. The cases of renaming that I’ve seen, were one way from Project Manager to Product Owner. That’s a pity as both are distinct roles which require different profile to fill the roles with quality.