1. A non-transitory, computer-readable storage medium storing program instructions executable by one or more processors to: detect that a runtime environment installed on a computer system is outdated, wherein the runtime environment is configured to manage execution of one or more code modules; in response to determining that a first code module was previously processed by the runtime environment prior to the runtime environment becoming outdated, allow the first code module to be processed by the runtime environment; and in response to determining that a second code module has not been previously processed by the runtime environment prior to the runtime environment becoming outdated, inhibit the second code module from being processed by the runtime environment.