Originally written by @tjboneman. Thank him!
Easily import this manually with Cocoapods.
pod 'MongoPredicate
This library is written in Objective-C but works well with swift
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"firstname CONTAINS[cd] %@", @"max"];;
NSError *error = nil;
NSDictionary *dict = [predicate queryDictOrError:&error];