  This paper introduces a new primitive to serverless language runtimes called
freshen. With freshen, developers or providers specify functionality to perform
before a given function executes. This proactive technique allows for overheads
associated with serverless functions to be mitigated at execution time, which
improves function responsiveness. We show various predictive opportunities
exist to run freshen within reasonable time windows. A high-level design and
implementation are described, along with preliminary results to show the
potential benefits of our scheme.
