Methods and systems are presented for custom caching. Application threads define caches. The caches may be accessed through multiple index keys, which are mapped to multiple application thread-defined keys. Methods provide for the each index key and each application thread-defined key to be symmetrical. The index keys are used for loading data from one or more data sources into the cache stores on behalf of the application threads. Application threads access the data from the cache store by providing references to the caches and the application-supplied keys. Some data associated with some caches may be shared from the cache store by multiple application threads. Additionally, some caches are exclusively accessed by specific application threads.