Macaulay2 is a system for computing in commutative algebra, algebraic geometry and related fields. The system was originally written by Dan Grayson and Mike Stillman. David Eisenbud joined the project a number of years ago, and many users are writing packages for the system, and some are contributing source code. See our web page http://www.macaulay2.com for more details, and binary releases. Report bugs via the github issue tracker at http://github.com/Macaulay2/M2/. This repository contains the source code for Macaulay2, and is intended to be checked out by developers of Macaulay2. The subdirectory "M2" contains everything needed by a user to build Macaulay2. The subdirectory "bugs" is where we keep track of bugs and new features. The subversion repository at svn://svn.macaulay2.com is kept up to date, although it does not see detailed commit messages from git commits.