Self-Hosted Go backend with BoltDB, Preact front-end. There is no built-in spam filter.

Congrats on the release. I'll have to give it a try. I've currently been kicking the tires on Commento [1] (which is also written in Go and MIT license where I can self-host).

Looking forward to trying out Remark42.

[1] https://commento.io

I'm seeking a library that enables inline comments and annotations within a document. Can anyone recommend something?

That's highly dependent upon what kind of document structure you want to embed inline comments into.

What type of document do you need this for? E.g. Word, Excel, Markdown, plain text, etc?

HTML. Say, a blog post. Or a technical document. Instead of comment threads at the bottom, I imagine the comments inserted/attached inline in the text, perhaps only visible with mouse hover or appearing in a sidebar.

author here, in case you want to ask me anything about the system

Any option for a non-JavaScript HTML/CSS front end?

Like https://mylittleforum.net/forum/? I am also looking for non-js + open source (self hosted) forums and I don't find much anymore.

PhpBB [0] was the king back in the days.

[0] https://www.phpbb.com/

Making such a frontend for remark42 with complete server-side rendering should be possible. In fact, even now the backend doing a lot of this, for example comments preview rendered this way.

Do you mean front end for mobile or desktop?

I meant server-side rendering for the web. Remark42 exposing all functionality via API and any alternative frontend can be made. I know someone doing android SDK for this. Not sure about ios side.

Why did you select BoltDB over SQLite?

The model it uses is non-relational and KV store was a better fit

Not questioning your decision at all, but can you explain the whole thought process which led you to the conclusion that it is a better fit?

I think it is a great start - the frontend seems a bit heavy for what it is, looks like a lot of thought went into the backend.