We reviewed Bridge Constructor Portal recently, and enjoyed it quite a bit. Awarding it a decent 7/10, we praised the way Portal's elements were interwoven into the Bridge Constructor framework, and as big fans of Valve's stellar first person puzzler, it was great to go back to Aperture Science and absorb that sinister atmosphere once again.

But while playing the game, we couldn't help but wonder how a small publisher like Headup Games wound up with the licence to one of Valve's most beloved series. To quell our curiosity, we reached out to Headup Games and Valve itself in order to find out just how the worlds of Bridge Constructor and Portal came together.

Jeep Barnett, one of the programmers hired by Valve to work on the original Portal (and subsequently its sequel), said that the idea came directly from Headup Games. "On their own initiative Headup Games created a prototype, complete with the Aperture aesthetic, and sent us a video. They also pitched a bunch of fun ways that Portal's mechanics could blend with a bridge building game," Barnett told us. "Their love of the brand was obvious from how much knowledge and polish they presented at such an early stage of development. Also, back in our college days, all of us from the original Portal team played the hell out of physics puzzlers such as Pontifex. We see the genre as a close cousin that inspired Portal, and we told them to go for it!"

However, according to Gregor Ebert, PR Manager at Headup Games, it took a little while to win Valve over. "After the initial idea came up from our boss (in late 2016 already), the guys from [developer] ClockStone Software gathered first level ideas and produced a concept video. We sent this over to our long-time business partner Valve, but as they are giving away their Portal license not freely (obviously), it took a few attempts and some month of time, but then they really liked the idea as well and agreed to the project."

With the project underway, the collaboration between Valve, Headup Games, and ClockStone Software continued, but the former company remained largely hands off. "Headup Games had the reigns during development, but frequently sent us builds to test," Barnett recalls. "We provided feedback for each build while giving them the freedom to develop their own vision for the game."

Ebert told us that, while Valve did take a backseat, it did help out when it came to writing. "The team of Valve ... was very supportive in regards to getting the best out of it, so we got help in writing the lines of GLaDOS and finding the right tone by Jeep Barnett, one of the creators of Portal 1 and 2, and they also helped us in technical

regards."

Barnett also spoke about Valve's input: "Near the end of development we tweaked the script and helped them secure studio time with Ellen [McLain, voice of GLaDOS]. We also directed them to a talented audio production specialist who's been creating GLaDOS VO within the fan community for years."

But what does Valve think of the final product? Barnett's final comment suggests it went down well. "They sent a nearly-complete version to us before release and it was a hit at the office and with our families."

It's interesting to see such a big company entrusting one of its high-profile products to a younger, smaller team, and we're glad we were able to get a small peek behind the curtain. We'd like to thank Jeep Barnett and Gregor Ebert for answering our questions.

Have you been playing Bridge Constructor Portal? Were you pleasantly surprised by this crossover game, or are you still waiting for that elusive sequel? Jump through a portal into the comments below.