Upsource

Upsource provides a web‑based interface for reviewing source code and browsing repository contents. It lets multiple developers inspect changes, leave comments, and discuss implementation details directly within the tool, supporting a shared understanding of the codebase. The system works across different repositories, allowing teams to navigate and compare versions without leaving the review environment.

The platform is aimed at development teams that need a centralized place to conduct code reviews and exchange knowledge about their projects. By presenting diffs, file histories, and annotations in a unified view, it facilitates collaborative decision‑making and helps maintain code quality throughout the development lifecycle.

Built by JetBrains, Upsource is positioned as a stable component of their suite of developer tools, integrating with the workflows of teams that already use JetBrains IDEs and other development environments.