In 2024, Fenris Creations – then called CCP Games – said that it was planning to make its Carbon game engine open source. Now, some two years later, the tech behind the long-running sci-fi MMO Eve Online is available on GitHub for everyone to use.
The open-source project is something that the company's core tech team has been working on at a "slow burn" for some time now, with the bulk of the work done in the last 12 weeks. Speaking to GamesIndustry.biz, Fenris Creations' senior development director for core technology, Ben Hunter, explains the reasoning behind it all. "We wanted to get the code out there for inspectability and building trust with the community," he says.
Ben Hunter | Image credit: Fenris Creations
"Fenris has a long history of building communities and engaging with them. If you look back to the early days of Eve Online, when we exposed our application programming interface (API), that was the start of our effort to engage with the community and let them build something with it. We arrived at this point two and a half to three years ago, where we decided there's nothing really special about our sauce in terms of the actual code. We, and the community, would be better served by actually getting it out there, having more eyes on it, so that we can actually learn and grow from that, and people can do crazy things with it, which we're very excited to see."
It's early days at the moment. Hunter says that things are "leaning towards" people using Carbon to build within the Eve ecosystem. Members of the community have already been submitting pull requests (PRs) – proposed changes to a codebase – for security fixes, and there's been chatter about someone making a web app to watch Eve Online content.
"We have to see how that manifests, but essentially, you can build anything with it," Hunter says.
Carbon is available in its entirety across a number of different modules. Most of the tech is under the MIT License, a popular and permissive option. Only two modules aren't under that banner: spatial audio clustering is covered by Apache License 2.0, while IO has a Python Software Foundation License.
None of these licenses has any commercial element; someone can use all of Carbon for free. They could make their own MMO using the tech, for free. They could even fork off the engine and build their own version, similar to how the Linux distro system works.
But making money isn't the point of this venture.
"It's about garnering the actual interest from people so that they want to invest their time, their effort, their money into contributing something," Hunter explains. "It's this belief that rising tides lift all ships. If we improve the code and we can all benefit from it, it's good for everyone."
Security concerns
Open sourcing creates a bit of extra work for the core tech team; they've got to handle PRs and monitor the changes. This is something Fenris has slowly been hiring towards for years now.
"We announced our intention to open source a couple of years ago, then throughout that period, slowly ramped up in some of the teams, not specifically for open source itself, but rather just to augment the teams so they'd have more bandwidth to handle the mechanics," Hunter says. "We have reserved time during our sprint process to review PRs, process them, and go through everything."
Eve Online launched back in 2003. | Image credit: Fenris Creations
There are many benefits to opening up your tech and letting anyone take a look under the hood. But bad actors are always out there, looking for any exploit they can find. Hunter says that security is "absolutely" a concern moving forward, adding that it's a pressure that ensures the team "increases the effort" they put in when reviewing code and making architectural decisions.
"But at the same time, the holes that were there would have been there anyway," he says. "Actually having the ability to have third parties contribute to and help us close any potential security gaps is very good. To be honest, for an engine that is 23 years old, the number of security-related PRs that we've had is quite minimal. That's eye-opening, in a good way – there's been a lot of work done over the years. As you can imagine, Eve Online has garnered a lot of interest over the years because of the scale of the fleet fights, the battles, and things like that. Nefarious actors, definitely, in the past, have wanted to probe that and try to disrupt it. There's been a lot of battle-hardening over 23 years to the infrastructural stack of the engine and the networking layer."
"The ability to have third parties contribute to and help us close any potential security gaps is very good"
As well as gameplay integrity, there's also the game's economy. Eve Online has a complicated, robust, and incredibly valuable in-game economy, with estimates suggesting a trading volume of more than $50 million per year. That part of the game isn't open source. In fact, Hunter says that a great deal of care was taken in deciding what was marked off for open source and what was not.
"We had to make very careful considerations for what we carved out and what we left off," he says. "Probably the hardest part of doing the open source project is deciding what genuinely is engine versus what is two decades of things that grew up around it, and then also rebuilding all of the pieces that were middleware or licensing that no longer would be applicable for open sourcing. That's definitely been a big part of the challenge."
Weighting from Godot
To help thread the needle, Fenris asked for advice from Godot – an open-source engine project that started in 2014 and that has seen substantial success in the past few years. Hunter notes that "the rise of open, permissible software is definitely a trend at the moment."
"The main conversations were around governance models," he continues. "We were expecting Godot to come in and have this playbook of how to govern an open source project at scale like that, but in reality, what it came down to was making the right architectural choices and having the architecture help protect and define the surface area for contribution. If you roll that down, that's a plug-in model for the engine, which is something Unreal and Unity have, and it's something we are currently implementing for Carbon at the moment.
We're moving to this plug-in architecture with our tooling. It's also something we'll be open-sourcing in the coming months. The biggest light-bulb moment in that conversation is that we can make some architectural decisions that will help with the actual operational governance of the open source project."
.jpg)
Ben Hunter says that Fenris Creations sought advice from Godot about creating an open-source engine. | Image credit: Fenris Creations
Regarding Carbon's governance structure, the project is fully permissible and open. Fenris is accepting contributions and putting together PR templates and contribution guidelines.
"We basically had our code ready to be open-sourced before we had some of the machinery in place to process the actual governance of it," Hunter says. "That work has all the details of how you can contribute, what criteria you have to meet when it comes to testing your work before it is submitted, and disclosing that you have utilised an LLM. We don't mind you using an LLM, but you have to disclose it because we may subject it to different scrutiny than if it were not disclosed."
Looking at the broader engine ecosystem, Hunter describes the landscape as "shifting quite considerably", pointing at Epic's recent announcement regarding integrating AI in Unreal Engine 6.
"We don't mind you using an LLM, but you have to disclose it"
"You're seeing a lot of the developers that were traditionally going to Unity or Unreal starting to shift gears a little bit towards Godot," he says. "If you look at Epic's recent announcements, they are shifting things quite a bit to ensure they can enter the LLM era. Unreal's been changing a lot of its foundations with the new Verse language and the Scene Graph replacing the Actor model to provide more persistence in large-scale environments. That's something that Carbon has been doing at scale for a very long time. It's something we've definitely seen the value in contributing to, and a lot of the other engines are starting to want to have their own pathway to this as well.
"There's a lot of re-architecting going on at the moment, but also the biggest part of this is figuring out the most useful way to integrate or utilise LLMs for workflows more than anything else. We ourselves also have a tools gateway that we've just created internally for LLM interfaces, which we are rolling out to the game teams in the coming weeks and after it's had a bit of hardening time, we'll be rolling that out as open source as well. There's definitely a shift in the industry at the moment."
Testing in the wild
Looking forward, Fenris Creations is going to be developing Carbon in the open. Anyone and everyone can look, and that's going to impact how the team works.
"The biggest thing is that we will be putting a lot more scrutiny into any bigger architectural changes that we make," Hunter says. "That's something that we now have to have much more consideration with the game teams because we will want them to do their own testing of that as well.
"The other, which will definitely change now, is we are seeing the need to create a test project. I don't want to call it a game, but it's an example game that is more for the testability and understanding the architecture and get started quickly in the engine. That's another thing that's changing a lot. We, as the core tech group, will have to create that test example, and that will become our test space, which will be our example project. Right now, when we make changes to the engine, we have to jump into Eve or Eve Frontier and try to test in those game examples. We don't have our own simplified example to run through."
Eve Frontier is a space survival game that integrates the crypto token $EVE. | Image credit: Fenris Creations
It's taken a great deal of work to get here, but now Carbon is open source, what does Fenris Creations want for its engine over the next five years? Hunter says that he hopes to see a large, "Eve-centric" community build up around the engine that will "create their own augmented versions of the game experience".
"If you look at history, when we released the API for Eve Online, we saw various side applications that helped you manage the skills of your character or fit the ship," he continues.
"With Carbon, we've given the capabilities and tools to the community, and the ability to make that a much richer experience is so much higher. But if you look at the direction of what Eve Frontier in particular is doing, where they're becoming a very open builder game, there's so much more potential there further down the road. I would say that in five years from now, we'd have quite a large community building a lot of infrastructure and apps and experiences around the Eve universe, as it were."
He concludes: "Of course, anything is possible with it being MIT-licensed, but I would like to see it contributing to the Eve universe as a whole."