> Seriosly, is this really a problem at all? Yes. I write Python and C everyday. I am highly proficient in both. I would quickly withdraw from a project that m

> Seriosly, is this really a problem at all? Yes. I write Python and C everyday. I am highly proficient in both. I would quickly withdraw from a project that mixes both in the same code base. I'd also be slightly alarmed to see someone claiming to be able to distinguish proper engineers and not being aware of the issue with multi-language projects :-) . My issue with multi-language project is that you introduce a lot of overhead to the process surrounding the code. The code-review / static analysis, build and test all requires an additional toolchain and associated best practices. It is already an issue with single-language projects to do this right, it quickly becomes a nightmare when you introduce an additional language. And that's without even considering the need of FFI integration or likewise, with possibly (preferably) framework to handle the generation of the interfaces, and thus the introduction of another dependency, a possible sub-par codebase with the associated bugs, and potentially very subtle bugs due to your objects not playing nice with the intermediate representation. I did it with a C++ / Java interface, never again. I would never greenlight such a project. This has nothing to do with the proficiency or the willingness to learn of your engineers.