Headcanon: like in real life, when two security programs get put on the same system, it’s tradition to immediately fight each other, and whoever wins gets to be the system defender. Like roosters.
… reminds me of one of the silliest (NSFW) Tron fics I ever read
Winner Take All by Fallowsthorn
be warned the “fight” is not exactly a fight
and it is RPF (Real Program Fic) with Avast, the real-life antivirus software, being personified as a somewhat insane pirate
(Tron fandom will always be amazing)