Combining programs to perform more powerful actions using scripting languages seems a good idea, until portability and parallel execution on computing clusters become the main concerns of the script. GNU Guix used GNU Guile as a domain-specific language to describe software packages. In the same way, the components that make up a workflow description can be expressed using GNU Guile.

In this talk I would like to present the work I have done to implement a simple workflow language and a workflow execution engine (both in GNU Guile) to run programs on computing clusters.