1. A method comprising: invoking, by an application executing on a computing device, a function call of a first function, wherein the computing device supports a bundled application library of functions and a native library of functions, wherein the bundled application library is represented in intermediate code and the native library is represented in machine code of the computing device; determining, by the computing device, that code for executing the first function exists in both the bundled application library and the native library; in response to determining that code for executing the first function exists in both the bundled application library and the native library, executing the first function using the code in the native library; while the application continues execution on the computing device, invoking, by the application, a function call of a second function; determining that, of the bundled application library and the native library, the code for executing the second function exists in the bundled application library but not in the native library; and in response to determining that, of the bundled application library and the native library, the code for executing the second function exists in the bundled application library but not in the native library, executing the second function using the code in the bundled application library.