Rust developer and Facepunch Studios founder Garry Newman said that prior to Rust, he was working on an online, Hitman-type game set in an open world similar to Grand Theft Auto.

The codebase for the prototype, called Cash4kills, eventually became Rust, the survival game which became immensely successful while still in Early Access. But Cash4kills was going to be very different.

“The one thing we don’t like about the latest Hitman games is that the game seems to be about finding out what the level designer wants you to do, rather than just working out the best place to kill a guy,” Newman told PCGamesN in an interview. “We wanted it to be all free-form, with bullet entry stats, bonuses for clean kills and for being unspotted, shareable replays, then cash rewards in a backend that you could use to buy new weapons, etc. So you’d only get one chance at a kill and if you f****d it up you couldn’t replay, you’d have to wait for the next contract via your real email.”

That sounds pretty cool, but the fact that Rust was based on a prototype with very different ambitions has created a lot of trouble for Facepunch.

If you launch Rust right now, you’ll be prompted to choose between “Play Rust,” and “Try Experimental.” The first option will lead to the game you’re familiar with that’s based on the prototype, and the second will take you to the experimental version, where Facepunch is changing “pretty much everything” with regular updates.

“There were a lot of stupid decisions made in the old codebase,” Newman said. “That’s probably unfair. There were a lot of decisions made when we didn’t know what game we were making… There’s a lot of systems that are integral to Rust, that are 3,000 lines long, that could be 100 lines long.”

Newman said he isn’t getting rid of the old version of Rust, but that all the team’s efforts are going into the experimental build, which will get more servers and become more stable as it grows.

For more on Rust, check out GameSpot’s previous coverage.

Emanuel Maiberg is a freelance writer. You can follow him on Twitter @emanuelmaiberg and Google+.
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