countPackage count contains 'counter' filters for all the gae services.
dscachePackage dscache provides a transparent cache for RawDatastore which is backed by Memcache.
featureBreakerPackage featureBreaker contains filters for dynamically disabling/breaking API features at test-time.
featureBreaker/flakyPackage flaky can be used to emulate flaky GAE errors that happen randomly with some probability.
readonlyPackage readonly implements a filter that enforces read-only accesses to services.
txnBufPackage txnBuf contains a transaction buffer filter for the datastore service.
txndeferPackage txndefer implements a filter that calls best-effort callbacks on successful transaction commits.

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