Replying to myself, for future searchers:

First, the latest patched version can be found at https://github.com/geofft/redshift

You may need autoconf, automake, and gettext. I used homebrew. I also had to run

  ln -s /usr/local/opt/gettext/bin/autopoint /usr/local/bin

to get the autopoint build-time dependency.

To get redshift to run at login, we'll use launchd. Save the following as ~/Library/LaunchAgents/redshift.plist (modify as needed if your binary and config files are elsewhere).

  <plist version="1.0">
   <dict>
     <key>Label</key>
     <string>redshift</string>
     <key>RunAtLoad</key>
     <true />
     <key>Program</key>
     <string>/usr/local/bin/redshift</string>
     <key>OnDemand</key>
     <false/>
     <key>ProgramArguments</key>
     <array>
     <string>-c ~/.config/redshift.conf</string>
     </array>
    </dict>
  </plist>

then run

  launchctl load ~/Library/LaunchAgents/redshift.plist

You can use

  launchctl list | grep redshift

to see that it's working. Thanks to http://developernotes.com/archive/2011/04/06/169.aspx