Setting up the infrastructure to manage a software project can easily become more work than writing the software itself. A variety of useful open-source tools, such as Web-based viewers for version control systems, "wikis" for collaborative discussions and bug-tracking systems are available but their use in high-energy physics, outside large collaborations, is small. We introduce the CEDAR collaboration's HepForge project, which provides a lightweight, modular development environment for HEP software. Facilities available include the above-mentioned tools as well as mailing lists, shell accounts, archiving of releases and low-maintenance Web space, all centrally backed up. HepForge also exists to promote best-practice software development methods and to provide a central repository for reusable HEP software.