Project Pythia recently went through an infrastructure overhaul. We spent months investigating, planning, and laying the groundwork to use MyST MD instead of Sphinx. JupyterBook is making a similar transition with JupyterBook2. Mid-June we spent a few days sprinting to officially make the switch!
Read more about the process and check out our new look at this blog post: Reflections on MyST-ification - Project Pythia