Nutika uses CPython as fallback. From the Limitations section:
> Standalone binaries built using the --standalone command line option include an embedded CPython interpreter to handle aspects of the language that are not determined when the program is compiled and must be interpreted at runtime, such as duck typing, exception handling, and dynamic code execution (the eval function and exec function or statement), along with those Python and native libraries that are needed for execution, leading to rather large file sizes.
Nutika uses CPython as fallback. From the Limitations section: