Update alternatives.md

[beorn]

Add more alternatives: InstantDB, ElectricSQL, SignalDB, PowerSync, SQLSync

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Describe the problem you have without this PR

Todos

• Tests
• Documentation
• Typings
• Changelog

[pubkey]

Some parts of these texts are wrong. Did you use ChatGPT?

[beorn]

It's a combination of ChatGPT and my own edits. Which parts are wrong?

[pubkey]

Its like everything is just slightly wrong a bit. Please write it by yourself.
As alternative we can just add a link-list at the bottom so that we at least do not missinform readers.

[beorn]

I'll go over it again and try to fact-check it more, and maybe make some entries a bit shorter. I wish there was another more comprehensive list of local-first technologies that you could point to, but this one is actually the most comprehensive I've seen so far :) In any case, it's useful to compare them to RxDB. It's also fast-moving field so my worry it'll be outdated very quickly.

[beorn]

I made another round of edits. It's somewhat difficult to compare and contrast the alternatives given they are so different and (often) flexible, and giving a pros/cons list is ultimately going to be a bit subjective. Perhaps there are other things you want to mention or leave out, or emphasize/deemphasize.

[beorn]

This comparison maybe interesting as it highlights internals of PowerSync and Electric-Next - https://www.powersync.com/blog/electricsql-electric-next-vs-powersync

[pubkey]

Thank you, this looks way better. Merged.