To install::

  pip install -r requirements.txt
  python setup.py develop

Add to your trac.conf::

  [components]
  multireposearch.* = enabled

Upgrade your trac environment::

  trac-admin path/to/env upgrade

Prepare all available repositories with an initial indexing::

  trac-admin path/to/env multireposearch reindex_all

You will now be able to perform text searches of repository contents through the trac search UI.

As long as you have your trac post-commit or post-receive hooks properly configured, 
source will remain up-to-date.

Otherwise, to manually reindex a single repository, you ca run::

  trac-admin path/to/env multireposearch reindex repo-name

Where repo-name is the name assigned to your repository in Trac.