The TaskCluster Worker is our latest worker, written in Go, which is intended to replace all other workers.
We wanted to write a worker that had a pluggable architecture, to make it super simple for people to create their own custom workers with their own feature sets, supporting arbitrary platforms, without needing to fork the worker codebase. This is achieved with a runtime discovery of plugins (worker features) and engines (supported environments).
The worker comes shipped with a default set of features and engines, which can be trivially enabled or disabled, in addition to any custom features and/or engines that the developer wishes to add, simply by adjusting the go build import paths.
For more information, see the reference section.