It looks like today I can spend some more time working on a roast plan design program I've been trying to make usable by non-programmers. The bits that I've already written were used to create things like this or the animated graphs in recent videos. The same code will eventually also get merged into Typica. A key differentiating feature is the ability to interpolate/extrapolate with relaxed cubic splines (no need to mess with control points that aren't on the curve).
The alternatives in use elsewhere are linear splines and Bézier curves. Bézier curves are too difficult to use and too easy to screw up. Linear splines are easy to use but unrealistic at the joints. Relaxed cubic splines are just as easy to use as linear splines but produce a more realistic plan by default.
I want to do this first as a stand alone thing first because that'll let me release sooner, but also because a tool like this is generally useful beyond just Typica. I want this to be usable for people who still do paper logging and I'm open to interop with non-Typica logging software.