From here you will find all relevant knowledge for contributing to Darcs.

Fix something in 5 steps

darcs clone --lazy http://darcs.net
*hack code*
darcs record -a -m "what my patch does"
darcs send
*send the generated patch file to patches@darcs.net *

The basics

• Getting Started Guide for new developers
• Understanding Darcs on wikibooks
• FAQ
• Tips

What to do?

• How to Help
• Ideas - The big ideas for the development of darcs.
• Probably easy bugs
• development list (darcs-devel) for contributing to (or observing) darcs development
• Regression Tests - Adding tests to the test suite.

Reference material

• API documentation for darcs (Haddock)
• Darcs Internals - Explanations on how various darcs subsystems work
• Coding Style

Digging deeper

Processes

• Release Management
• Buildbot
• Policy
• Hacking Sprints

Current Status

• buildbot status
• TODO code coverage in tests (out of date; see issue1940)