Is the collective.elasticsearch package widely used as it is? I am working on a branch that works with the newest stable release of elasticsearch (6.3) and am unsure if I should create a pull request or if we would need to fork the package. I am working closely with @tkimnguyen on this.
please do not fork it; do your work on a branch and create a pull request.
BTW, I think @claytonc was also working on this, but I don’t know if he has some branch to show.
you could collaborate with him also.
We would be interest inn trying your branch. We are need the field folding
feature in later elastic search. We are interested in adding a feature to
customise the search query per site or per request.
I took as a base that  and updated the client for elasticsearch 
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