> So I suppose the project being a side project to learn a new language.

Perhaps. But the author Minoru Osuka ain't nobody[1]. He is

- Engineer at Mercari, Inc.

- Committer at Apache Software Foundation

- Co-author of a Apache Solr book in Japanese

- Ex-Yahoo! JAPAN

- Ex-Rakuten

So yeah, I think he knows what he's doing.

[1] https://twitter.com/minoru_osuka/