Python
My go-to language for personal projects.
Javascript
I've also worked with Typescript.
Scala
Downside is that I now rely on IntelliJ.
HTML and CSS
Ironic that the industry's tool of choice for UIs was originally designed for static content.
Git
I've been complemented on my descriptive commit messages a grand total of once.
My limits
and when to ask for help.
Designing and implementing programming languages
Property-based testing
Ethical work practices
Monads
(monoids are alright too I guess)
Seeing my work improve people's lives
Peeking behind the curtain to see how things work