Right now the default functionality is that each tag requested is treated as an "AND" requirement.
I'd like to write a lexer to support more complex queries. Similar to SQL or other AND/OR/NOT lexers.
"foo AND bar OR blah AND baz NOT duh"
You get the idea.
A solid lexer example to follow possibly: https://github.com/eliben/code-for-blog/blob/master/2014/tablegen-lexer-go/lexer.go