Looks pretty clean.
If you want a fun feature to build, add tiny sparkline graphs. Maybe pressing z/x/c/v can switch between last hour/day/month/year charts on each stock item.
Check out https://github.com/holman/spark for how to make graphs with simple character glyphs.
I realize my problem with terminal programs like this is that I forget to ever use them. That's why I prefer something like a macOS menubar app that I can toggle to run at startup.
My only complaint is it's always going to be 15 minutes behind if you're using public sources, otherwise I love it!
If you don't mind, can you explain the difference between this type of Post and a 'Show HN'? Is it that this one was not submitted by the person who built it whereas the requirement of Show HN is that the submitter must be personally involved in the project?
> What are Ask HN and Show HN?
> Ask HN lists questions and other text submissions. Show HN[1] is for sharing your personal work and has special rules[2].
[0]: https://news.ycombinator.com/newsfaq.html