 DragonFly BSD is a free and open source Unix @-@ like operating system created as a fork of FreeBSD 4 @.@ 8 . Matthew Dillon , an Amiga developer in the late 1980s and early 1990s and a FreeBSD developer between 1994 and 2003 , began work on DragonFly BSD in June 2003 and announced it on the FreeBSD mailing lists on 16 July 2003 . 
