[mattbillenstein]

Mongo is much maligned here and I hesitate to even comment for fear of attack, but in my mind it has some compelling use cases and after Wired Tiger became the default storage engine, that pretty much solved the issues with compaction I had seen in the past while delivering a lot more performance.

I've built systems with it where we didn't own the schema - we were scraping data from other places and schemaless was a feature. And I benchmarked it against Postgres and a couple other things and I just couldn't get the same performance - note our operations were idempotent to the db, so even in a hard crash, we could just re-run the scraping job and we wouldn't really "lose" any data -- or even if the data was stale by a day, not a big deal... That system would do tens of millions of upserts per night on not crazy AWS hardware and it ran for years like this without problems.

Would I use mongo for situations where I needed transactions? Almost never - I actually like Postgres a lot and it's my default for your run of the mill CRUD apps since you can do geo, crypto, search, etc by just installing a few extensions. Do I got on HN on every mongo article and bash them constantly? No, I think they've built a pretty decent thing if you understand the implications of not confirming writes to replicas and whatnot and tune it to your needs.