Hi Adrian, We have been contemplating some ideas around your requirements. Are you working with several "types" (as defined by ProtoBuf files) or only one such type per one of your caches (and thus afaics SearchFactory)? In case of the latter, one idea would be that you always target your generic entity type with your queries and we provide an SPI which allows you to configure the field bridges to be applied for the individual fields of a given entity (here always the generic entity type), e.g. FieldBridge getFieldBridge(Class<?> type, String fieldName). We could then query this SPI from within the HSEARCH-based parser backend to apply the right field bridges for a given query. You would create any FieldBridge instances yourself and thus could inject whatever data you need into them. Would this address the needs of Infinispan? If you need to work with several ProtoBuf types per SearchFactory, we'd have to do some more changes within HSEARCH, as the metadata essentially is keyed by class type atm. and we'd have to change that to key by a more type representation. Thanks, --Gunnar 2013/8/31 Emmanuel Bernard <emmanuel(a)hibernate.org&gt;