I am working on [1] a modernized open (AGPL) stack for interactive tutoring systems. SRS++, with hooks for defining your own pedagogical protocols over knowledge dependency graphs, Elo rating systems, etc, and with an eye toward gracefully differentiable curriculum that can hill-climb in terms of its efficacy.

With this stack, I'm scaffolding several (fingers crossed) commercial learning SaaS products. The first [2] is LettersPractice - a minimalist early literacy app that's family-first, in so far as it presumes an adult supervisor who co-learns strong confidence as a phonetic coach both at and away from the app. Putting considered rails on the parent-child reading experience.

The second set of apps is in music, with some experimental dev right now against piano (via midi devices), flute [3], aural skills, and sightsinging.

[1] https://github.com/patched-network/vue-skuilder , https://patched.network/skuilder

[2] https://letterspractice.com

[3] https://flutor.app/