  Software Heritage is the largest existing public archive of software source
code and accompanying development history. It spans more than five billion
unique source code files and one billion unique commits , coming from more than
80 million software projects. These software artifacts were retrieved from
major collaborative development platforms (e.g., GitHub, GitLab) and package
repositories (e.g., PyPI, Debian, NPM), and stored in a uniform representation
linking together source code files, directories, commits, and full snapshots of
version control systems (VCS) repositories as observed by Software Heritage
during periodic crawls. This dataset is unique in terms of accessibility and
scale, and allows to explore a number of research questions on the long tail of
public software development, instead of solely focusing on ''most starred''
repositories as it often happens.
