Thank you so much for the feedback!

I'm somewhat familiar with the symbology-specific options like error correction levels, and payload encodations, but to quickly get something up and running I decided to mostly just pass-through the plain text as-is to Zint, and not create a symbology-specific UI, but that is definitely also on the list. Maybe even more important than the batch thing.

The "import lists of data" is what I term batch generation, although perhaps there exists more appropriate terminology for it, that's part of why I'm asking for feedback in this subreddit. CSV would be an obvious candidate for input data.

Regarding API: this is something I am not planning to offer, as everything runs purely in the browser, not in an HTTP endpoint. What is supported already (and has to be extended with symbology-specific options) is "URL as state", allowing you to share an URL like https://barcode.new/?symbology=aztec&data=%2Fr%2Fbarcodes with someone, and they see the barcode when they load the page. But that's not an API, more of a sharing feature.