My list looks like this
data science:
* I liked the Kiba ETL (Ruby), I used it with Rails and Thor and was rather happy with what I could do.
* I used Tableau for BI but I would recommend Apache Superset instead.
* Luigi (Python) was also interesting but I didn’t do much with it (yet).
* Jupyter, Anaconda, Pandas ... The standard Python data science stack has gotten a few nice tutorials in the last few month I would like to go through.
web frameworks:
* NestJS is a sane framework for Node.js, sort of like the default libs stitched together. Annotation based routing is the oddest thing about it but I would still go with it if I would start a new app for Node.js.
* Ruby on Rails 7. Lots of nice small stuff coming out of Rails over the last versions. I am sort of lo key excited.
* Finally look at elixir, phoenix live view.
system programming:
* Still need to read Powerful Command-Line Applications in Go.
bonus:
* Learn Rust (webasm toolchain looks nice, can use with deno (a Node.js replacement with some promise but still rather young))
* Play with Groovy (and modern Java) when Fedora 36 (for Java 17) and Groovy 4.0 is out.