1. A non-transitory electronic-device readable storage medium storing instructions, the instructions comprising: one or more instructions that, when executed by a processor, cause the processor to: accept a specification of an accessed class, the accessed class supporting a plurality of features that provide information or functionality on behalf of the accessed class, wherein the plurality of features comprise: a first set of features for which access rights are specified, and a second set of features for which access rights are not specified; accept specification of the first set of features, specification of the first set of features comprising: an identity of one or more protected features in the first set of features, and an identity of a specified accessing class to be granted access to the one or more protected features in the first set of features; and enforce access rights for executing code, the enforcing comprising: receiving a request to access a requested feature of the accessed class by the specified accessing class, determining whether the requested feature is in the first set of features or the second set of features, allowing the specified accessing class to access the requested feature if the requested feature is determined to be in the first set of features of the accessed class, and preventing the specified accessing class from accessing the requested feature if the requested feature is determined to be in the second set of features of the accessed class.