1. In a caching environment, the cache responsive for storing recently computed function results as values operable for satisfying successive invocations of the function, a method of verifying cached computational results, comprising: storing a computed function result as a cached value in a cache; upon receiving a subsequent invocation of the function, examining a duration of the value in the cache; comparing, based on expiration of a staleness detection threshold, a result of a subsequent execution of the function to the cached value in response to the subsequent invocation of the function, further comprising comparing a hash based on the subsequent invocation of the function to a set of hash values corresponding to a plurality of cache values; identifying a matching hash value in the set of hash values based on the hash comparison; comparing a duration of the cache value corresponding to the matching hash value to the staleness detection threshold, the duration defined by a previous execution of the function; recomputing, if the duration exceeds the staleness detection threshold, a result from execution of the function for validating the cached value; returning, if the duration of the cache value is within the staleness detection threshold, the cache value as the result of the subsequent invocation; and flagging an error based on the duration and the staleness detection threshold if the result differs from the cached value.