ihaskell VS Gitit

Are you referring to IHaskell: https://github.com/IHaskell/IHaskell?

Note that we do have the IHaskell kernel for Jupyter, so we don't have to be that jealous.

More info: https://github.com/gibiansky/IHaskell/issues/1251

That looks like a generic front-end error for when the back-end is unavailable, the back-end error should be more informative, but I don't know where exactly you can find it. At this point it might make sense to open an issue on the issue tracker of IHaskell, they will be able to give you more useful answers.

I haven't actually used IHaskell, however, the png file is presumably created in whatever the working directory is when the script is running. The IHaskell wiki says:

You're correct.

It says at the bottom: powered by https://github.com/jgm/gitit

Readme states that: "Gitit is a wiki program written in Haskell. It uses Happstack for the web server and pandoc for markup processing."

I’ve used the Gitit Wiki. Database is plaintext markdown files under git source control. Renders with pandoc so you get a really good dialect of markdown. The look and feel is a little dated but 8/10 highly recommend.

I don't use gitit, but I've had people advocate it to me: https://github.com/jgm/gitit

Instead of SQLite I would prefer if you stored the snippets in a git repo like Gollum or Gitit.

I use my own forked version of gitit (dark, full-width theme, with automated toc and some other tweaks) for the last 5 years or so which looks and functions quite similarly. I handled web bookmarking/clipping with xclip (rich text clipboard) + pandoc html-to-markdown.