Tubul is a static CMS tool with three simple goals:
Tubul will be simple to install and to deploy. Lightweight refers to the design goal to produce minimal html5 files to run on very low requirement servers. Opinionated means that Tubul will only support one templating language, one syntax and one language. Tubul is not a general purpose solution but a specific tool.
And yes, the wheel is being reinvented. I like making my own printing press!