Logos for the rules. Sphere for everything those rules touch. The two halves are doing different work and the name keeps me honest about which is which.
Software rasterization where it earns its place. A schema-driven game layer where it earns more. Worlds, characters, items, zones: all entities, all derived from the same ontology that runs the rest of my projects.
Slow build. Deliberate. The engine matters less than the world you can describe in it.