9. A computing device comprising one or more processors and one or more memory devices comprising program instructions that when executed by the one or more processors cause the computing device to perform operations comprising: parsing a first collection of statically-typed executable machine-readable code to locate descriptions of one or more application programming interfaces (APIs) included in the first collection of statically-typed executable machine-readable code; transforming the descriptions of the one or more application programming interfaces of the first collection of statically-typed executable machine-readable code into an alternate form; and checking compatibility of a second collection of dynamically-typed executable machine-readable code with the first collection of statically-typed executable machine-readable code using the transformed descriptions of the one or more application programming interfaces of the first collection of statically-typed executable machine-readable code to verify that call sites of the second collection of dynamically-type executable machine-readable code map to the alternate form.
10. A computing device as described in claim 9 , wherein the checking compatibility of the second collection of dynamically-typed executable machine-readable code comprises consuming the transformed descriptions of the one or more application programming interfaces of the first collection of statically-typed executable machine-readable code by the second collection of dynamically-typed executable machine-readable code.