I first discovered Alexandria in early February: https://git.sr.ht/~seirdy/seirdy.one/commit/935b55f10f9024ee...
Around the same time, I also discovered sengine.info, Artado, Entfer, and Siik. By sheer coincidence they all were mentioned to me or decided to crawl my site within the same couple weeks. So yes, from my perspective there have been more than a few new smaller engines getting active on the heels of bigger names like Neeva, Kagi, Brave Search, etc.
The biggest thing I've found is that when doing technical searches it always turns up the sources I'm actually looking for, actively filtering all the GitHub/StackOverflow copycat sites.
It also seems to up-weight official docs compared to Google. For example, "how to read a json file in python" turns up the Python docs as the second result, where in Google they're nowhere to be found.
1. free version is curated topic filters that sit on top of Google -- best on laptop or desktop at moment / iterating mobile due to ad splash; it's unclear due to TOU that we can ever make that fully server-side legally, though do so have some things testing to see if free version can be ad-free or more tracking free
2. premium version will be mix of our scraping and Bing, depending on topic - standard web search via Bing + same curation as (1), closer to real-time for us
3. have tested out most other indie indexes or sites, for full web scale, money is on ahrefs or brave giving bing / google run for it
4. our primary emphasis is on bringing back some of the Yahoo! directory or Alta Vista look & feel of drilling into topics, so balancing 1-3 (^) as best we can atm, small team, fully bootstrapped modulo tiny F&F round
5. also @DotDotJames on twitter, still iterating when add team info to site
Try comparing results with a Bing-based engine (e.g. DuckDuckGo) or a Google-based one (e.g. StartPage, GMX) to see if they differ. (Don't use Google or Bing directly, since results will be personalized based on factors like location, device, your fingerprint, etc.).
I'd like to try them out, could you mention which?