I like Janet a lot, and have been using it for small personal projects for about a year.
But it does come with some design decisions that I'm a bit ambivalent about and for which I haven't found a good explanation:
- No persistent data structures. I guess this has something to do with limitations of the GC?
- unhygienic macros combined with lack of namespaces. XOR those two choices would be fine, but the combination is janky
- Somewhat peculiar choices in syntax. It's neither Scheme, nor is it Clojure. # starts comments, ; is splice, @ marks literals as mutable...
Janet is very small, apparently smaller than Lua, and is also intended to be embedded into native-code programs. Hence, I suppose, the decisions that make it "too" simple: it apparently is not intended for writing large amounts of code.