I have a language I wrote for processing data pipelines. I’ve used it for years, but I can count the number of users on one hand. I wrote it partially to learn about writing a scripting language, partially because Nextflow didn’t exist yet. I still use it now because it works much better for my way of processing data on HPC clusters.

The only code that exists on the internet for this is test data and a few docs in the github repo. It’s not wildly different from most scripting languages, from a syntax point of view, but it is definitely niche.

Both Codex and Claude figured it out real fast from an example script I was debugging. I was amazed at how well they picked up the minor differences between my script and others. This is basically on next to zero training data.

Would I ask it to produce anything super complex? Definitely not. But I’ve been impressed with how well it handles novel languages for small tasks.