The key to writing a PL and surviving is to have an exit strategy. Figure out ahead of time how long you will spend on this project, otherwise it’s liable to last half a decade or more before your interest wanes.
PL design is like crack for programmers. It is a lot of fun, which is why you see hundreds of little languages posted here every month.
The danger is that some people get don’t have a clear idea. About what it takes to write a pl. They can get quick wins with a parser generator and maybe some easy semantics, which give a good taste of how fun PLs are but also belie the fact that the hardest parts are exponentially harder than that.
Anyone embarking on a PL needs to be clear eyed about a few things.
1. You’ll never make money off of it. No one sells compilers anymore, and there are like 2 big for-profit languages out there out of thousands. If you do make money, let us all know how.
2. The odds are your language will have exactly one user, yourself. Get comfortable with the possibility you will spend years on something and no one will really appreciate it.
3. The real work in creating a language is not technical but community building. Languages need people who speak/write it to thrive, so as much or more work needs to be put into the community effort for the language to succeed. If all you want to do is work on technical problems that’s fine, but technical prowess doesn’t make a language popular.
4. Get ready for criticism. Every programmer has their opinions about languages and they will be sure to tell you their opinion of your language. It will not be good. The only people who will appreciate your language are other language designers. Most everyone else will start by telling you how you’re doing things the wrong way, and they’ll end by asking why you’re eating your time with all this anyway. Get ready for that and steel yourself against it.