I find it interesting that after all these years of HN, commenters still ignore the main topic of the OP (a calculus book) to focus on the language it's written in

Please don't respond to a bad comment by breaking the site guidelines yourself. That only makes things worse.

https://news.ycombinator.com/newsguidelines.html

"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

https://news.ycombinator.com/newsguidelines.html

Note that "The benchmark data shown above were computed with Julia v1.0.0" (2018)

LuaJIT is only appreciably faster on text ingestion and printing in those benchmarks. Julia is also plenty general purpose, just targeted (initially at least) towards the numerical community. LuaJIT is fantastically impressive though.

Now they need to include .NET and System.Numerics.Tensors but that would make a lot of popular options look bad :)

(particularly go which has no business being used in this area)