Pak - a library written in Python used for embedding hyperlinks into different types of digital media, such as video, audio, and text.

Factor includes a large standard library, written entirely in the language.

Third-party libraries written in pure Python may also be uploaded.

Miro is mostly written in Python, although it links to various libraries written in a variety of languages.

Support for Gadu-Gadu is provided by libgadu, a library written in C using reverse engineering methods.

LiveCode has around 1,900 built-in language terms and keywords, which may be extended by external libraries written in C and other lower level languages.

Some wrapper libraries exist to act as a bridge between a client application and a library written using an incompatible technology.

It is not possible to create user-defined data types without using a library written in assembly.

CPython is distributed with a large standard library written in a mixture of C and Python.

It uses the S-Lang library written by the same author, John E. Davis.