C is one of the most known programming languages. Its key features include ‘simplicity’, unfriendliness and lack of many helpful abstractions. Overall, it is a nice experience.
Cosmopolitan makes C a build-once run-anywhere language, similar to Java, except it doesn't require interpreters or virtual machines be installed beforehand. Cosmo provides the same portability benefits as high-level languages like Go and Rust, but it doesn't invent a new language and you won't need to configure a CI system to build separate binaries for each operating system. What Cosmopolitan focuses on is fixing C by decoupling it from platforms, so it can be pleasant to use for writing small unix programs that are easily distributed to a much broader audience.
Там есть очень прикольные хаки в си!