Elastic Enterprise Search

It is just the best back end for search engines in the market. A NoSQL database that is trustworthy. Also, it is open source. Incredibly easy to use.

Mostly for developers: other people would have a hard time with it.

The fact that Elasticsearch offers really efficient & quick querying of data without a compromise on the different range of queries it can support is really awesome, also Elasticsearch can rank matching documents based on matching criteria which is also very useful. Elasticsearch also handles distributed queries very efficiently.

Reindexing documents can be a real pain if there is a major change in the schema, otherwise no complaints.

Federated search across multiple platforms

The implementation was bad. The cost to implement to get anything close to what I would get with Algolia or Coveo is approximately 10 times the cost of the software.

Elastic search has completely changed how we can fetch and visualize our customer's data. With the advanced text indexing, we can easily build a text search engine which gives accurate results. The powerful query format allows us to construct complex queries from deep filter trees and aggregate data in any way we want. Most importantly, all of this is extemely fast - giving results within milliseconds when working with complex queries on milions of documents. If performance ever becomes a problem, Elastic search is easily horizontally scalable and therefore future-proof.

One critical thing I'm missing is a proper way of handling migrations. If you for example need to change the format of indexed documents - and therefore the mapping, you need to develop your own way of programatically handling the reindexing - or do it manually.