TocSim Home Page

Welcome to the TocSim Home Page! TocSim is a Theory Of Constraints based process simulator. It can be used to model most processes, including software development projects, business processes, manufacturing processes, etc., and display results as animated graphs and text reports.

TocSim was originally developed to model software development processes. In particular, to demonstrate how statistical fluctuations, batch sizes, and unit testing affect productivity. These effects can be rather counter-intuitive. For example, small random fluctuations in productivity at different stages in a process can reduce productivity quite substantially. This is a common reason why projects miss their deadlines. When this happens, it is often wrongly attributed to poor estimates, or some other cause. Another counter-intuitive effect that tocSim has been used to demonstrate is that the size of batches in a project (iterations, delivery cycles, test cycles, etc.) etc., have a very large effect on the overall productivity. Project velocity increases when batch sizes go down. This effect, and its causes, have been well known in Lean Manufacturing since the fiftes. In the IT business, managers and development teams who understand the effects are rare.


2006-03-13: Code in the Repository

TocSim now has some working code in the repository. It is pre-alpha code. The framework works (except for batches), but it is rather raw and unpolished.