The original Tendermint implementation provided a fixed, built-in event
indexer, but users would like to plug in different indexing backends. Although
ADR-065 was a good first step toward customization of indexing, its
implementation model does not satisfy all the user requirements. Moreover,
this approach leaves some existing technical issues with indexing unsolved.
This RFC documents these concerns, and discusses some potential approaches to
solving them. It does _not_ propose a specific technical decision. It is meant
to unify and focus some of the disparate discussions of the topic.