Road To A Distributed Search Engine by Shay Banon.
If you are looking for a crash course on the construction details of Elasticsearch, you are in the right place.
My only quibble and this is common to all really good presentations (this is one of those) is that there isn’t a transcript to go along with it. There is so much information that I will have to watch it more than once to take it all in.
If you watch the presentation, do pay attention so you are not like the person who suggested that Solr and Elasticsearch were similar. 😉