External References
Mill comes bundled with a set of external Open Source libraries and projects.
OS-lib
OS-Lib is a simple, flexible, high-performance Scala interface to common OS filesystem and subprocess APIs.
Mill uses OS-Lib for all of its file system operations.
uPickle
uPickle: a simple Scala JSON and Binary (MessagePack) serialization library
Mill uses uPickle to cache target output to disk as JSON, and to output JSON for third-party tools to consume.
Requests-Scala
Requests-Scala is a Scala port of the popular Python Requests HTTP client. Requests-Scala aims to provide the same API and user-experience as the original Requests: flexible, intuitive, and straightforward to use.
Mill bundles Requests for you to use to make HTTP requests.
MainArgs
MainArgs is a small, dependency-free library for command line argument parsing in Scala.
Mill uses MainArgs to handle argument parsing for `T.command`s that are run from the command line.