The PostgreSQL source code is stored and managed using the Git version control system. A public mirror of the master repository is available; it is updated within a minute of any change to the master repository.
Our wiki, https://wiki.postgresql.org/wiki/Working_with_Git, has some discussion on working with Git.
Note that building PostgreSQL from the source repository requires reasonably up-to-date versions of bison, flex, and Perl. These tools are not needed to build from a distribution tarball, because the files that these tools are used to build are included in the tarball. Other tool requirements are the same as shown in Section 15.2.
If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.