Maybe, I dunno, we should first focus on making this Earth habitable long-term?

A group of 3d printer owners in Warsaw, Poland, has delivered ~4000 shields to the local hospitals here, over the last 2 weeks. And nobody else did in this time frame - not the gov, not the companies with injection mould setups, nobody. So in this particular situation I'm pretty sure we saved at least someone's world - the ER staff and doctors who didn't get infected thanks to these shields.

Was this the most efficient way to go about it? Absolutely not! Did we save the whole world? No, we didn't. But in situations like this every little bit helps.

Great, now Earth is going to deflate ... :(

Dear AC,

I'm not sure what version of Lucene you used, but as one of the Lucene committers I can assure you of the following:

* queries can start with a wildcard - although this is not supported by the standard QueryParser. The reason is that the cost of such queries is high, and I bet you can see this difference in Spotlight too.

* it's true that Lucene queries cannot contain just a NOT clause, but you can easily prepend a clause containing a MatchAllDocsQuery to get the same result.

* Lucene indexes do support incremental updates, they have from the day one. Updates are usually batched for performance reasons, but if you want you can add a single document to an existing index and all will work fine. The usual strategy (which I suspect Spotlight also employs) is to keep a small in-memory index for small updates, and flush it to disk only after it reaches N documents, at which point an on-disk merge occurs.

* WildcardQuery is translated into (possibly) enormous boolean OR queries, but RangeQueries are not. I'm pretty sure that someone concerned about the performance of WildcardQueries (which are normally rarely used) can come up with a tuned implementation of the Scorer that doesn't expand the query into multiple boolean clauses.

* numerous leaks? for any definition of "numerous" I think it's an overstatement. There have been something like 2 or 3 leaks detected over the last 1 year, IIRC. If you know about any other leaks, why don't you report them, to make Lucene "less f*cking disgraceful" ??

And finally, regarding the open/closed source issue: how many innovative applications have you written using the Spotlight engine? Running on Linux/Windows ? I thought so ... Whereas there are hundreds of applications, both closed and open source, which use Lucene. I guess that my point here is that it's not just the sheer performance that counts.