Didn't read this one, I don't have much time to read these days. But we definitely need more hands on practical information to counter the avalanche of academic fluff out there, and many seem to enjoy Crafting Interpreters.
Having spent 34 years writing code and around three years full time designing my own languages, most other kinds of code make me fall asleep sitting up these days. Nothing really compares to controlling your world from the outside.
Lately I've been working on a stack machine devkit [0] to use as foundation for new languages, providing convenient access to most of what's needed and an integrated assembler to control it from the outside. The general idea is that you link the library and hook in a custom reader for your syntax, possibly embedded as a separate opcode. It's 5kloc of reasonable MIT-licensed code, small enough to own.
Feel free to have a look and I'll try to answer any questions.
[0] https://github.com/codr7/cidk
Edit: Was it the academic toes? Because I'm just sharing some code I wrote to help people get started designing their own languages. What did you do for others without expecting anything in return lately?