- focus of project seems admirable (teaching / learning)
- long-term viability
- multiple core developers - less "bus factor one"
- core developers are working on the project at least partly as part of their day jobs (academics)
- moved to being on top of chez scheme (which also has other devs)
- development by similar members over long period
- main members seem mostly decent [1]
- conceptual integrity seems to be relatively important
- documentation seems on the good side
- errors exist but prs appear to be welcome
- readable papers, posts, audio, and videos by various authors exist about portions of the system
- these have existed for a number of years and it doesn't look like this will stop anytime soon (older videos have worse quality but this may be true for many such things)
[1] there is one clear example of someone whose manner of interaction has not been great at times, but it's possible there may be improvements along these lines