I'm not sure why you're getting downvoted. It might be hitting too close to home for some. But yeah, 95% of developers choose things to do to boost them for the next job.
This applies here as well. Typescript could go a long way.
But admittedly, writing a grammar, parser and then a whole compiler along with its tooling of a new DSL is fun for sure but does look good on CV as well.
I didn't say anything more than that.