The AI for the garbage trucks has been rewritten.

This is not the premise for a rubbish dystopian sci-fi movie. Browsing through the Steam Workshop section for Cities: Skylines – the surprise hit city-builder with an enormous fanbase of disillusioned SimCity fans and devotees of Colossal Order’s previous series, Cities in Motion – we’ve found a free mod that offers an essential, if unglamorous, service to the citizens of our sprawling, glass-and-chrome metropolis.

“Oversees trash services to ensure that garbage trucks are dispatched in an efficient manner,” reads its description, modestly. A thankless, humble, yet noble task – all the more so considering it’s a fan project.

“We don’t have that much information on who the modders actually are,” says lead designer Karoliina Korppoo, when we ask who it was that was so dissatisfied with the game’s vanilla trash collection AI that they decided to write their own. “But based on the forum discussions and what I’ve seen people do, all I can say is that they are really dedicated, creative and highly efficient people. They’re so fast at making the mods, that when we are [thinking], ‘maybe we should do something like this,’ they have already done it and released it and even iterated on it. If we are working on a fix for something and our version is still in testing, because it takes a long time to get content out to the players, I will just guide them to use the mod which does the same thing.”

Cities: Skylines, with its appeals for community feedback and involvement in practically every video on its site, appeared at almost exactly the right time. After the disappointing release of 2013’s SimCity, with its often-impenetrable servers and claustrophobic map sizes, Cities: Skylines is as much of a point-for-point rebuttal to EA’s fleecing business practices as city-building fans could ask for. And the mods are just the start of it.

For one thing, there’s no online component – a massive coup for players who only ever wanted to raise a megalopolis on their own terms, without being pressured to deal with in-game neighbours or the now defunct Maxis’ inadequate server farm.

“We feel that the city is your domain, it’s your creation. You don’t want anybody messing with that,” says Mariina Hallikainen, Colossal Order’s CEO. “Some people want to have multiplayer where they can build the city together…There are even people who are sharing their save games. It’s like, ‘you continue from here and give it back to me tomorrow and we’ll see where we are.’ It’s really amazing! It’s like a poor man’s multiplayer. I do understand it is appealing, but for us, having such a small team, I think [true multiplayer is] way too ambitious to think about at this point. We’re definitely focusing on a singleplayer experience, currently.”

Another oft-vaunted feature is the game’s map size. We’re not cartographers, but it’s big. Every time your wind farms, garbage dumps or industrial district starts bulging at the borders of one plot, the game pings you with a message that a new area has, conveniently, been made available for purchase. A few grand later, and – ping! – you’ve got another vast expanse of beautiful, unsullied greenery to steamroller over and fill with coal power plants and tenement blocks. Take that, green belt development restrictions.

“In 2013, what [SimCity fans] wanted was a new SimCity, and the game that they got was not that SimCity-like,” says Korppoo. “I think one of the features that for me was important was just that the map size was so, so small. This was something that we really needed to [fix]. Any time in SimCity when you unlocked something, you’d gain this new awesome building, but then you’d have no place to put it. And that kind of takes the whole fun out of actually gaining something, when you can’t actually use it.

“Or if you can use it, you have to bulldoze a large area for it first. This was really kind of something that said to me, ‘we should avoid bulldozing stuff as much as we can’. Because the player has worked to create something, and if they are kind of guided to destroy it, the whole work is lost and it’s not fun.”

Cities: Skylines © Colossal Order

But Cities: Skylines was, its creators say, never intended as a shrewd capitalisation on SimCity’s shortcomings. The truth, as the developers tell it, is much less conspiratorial: the game was always designed to be an old-school city-building experience. That EA and Maxis’ decision to take that experience and crowbar in multiplayer drove players to Cities is just an (admittedly happy) coincidence.

“We basically have been planning a city-builder since we started the company back in 2009,” says Hallikainen. “So it’s not – or at least, I want to believe it’s not – only a response to the failure of SimCity. We really took inspiration from the classic city-builders. I think [EA and Maxis] tried to tap into an audience that is more, I think, the kind of [common] player-type we have today. But we really just wanted to bring the classics to the modern day.

“I think there were a lot of things to be learned from SimCity, but if you think about the player control, the sandbox gameplay – those were the sorts of things that were very important to us even very early on in the project. We did not design the game as a reaction game to SimCity.”

But the clearest divergence in thinking between Maxis and Colossal Order’s thinking is in the latter’s approach to mods. Where EA’s defence of an always-online experience can be read (charitably) as controlling (and ditto its restrictive modding policies), Cities: Skylines was built from the ground up to be cracked open by players and tinkered with. To date, there are more than 40,000 mods available for the game through the Steam Workshop. Some add new buildings, some tweak the game’s inner workings, and some simply remove features that… didn’t prove as popular as perhaps the developers expected.

“I think even before the release [the thing people most disliked] had to be the Chirper, the little blue bird,” says Hallikainen of Cities’ in-game Twitter parody, which like its real-world counterpart sometimes trips over the line between helpful and deeply irritating. “Funnily enough, it has been one of the bigger issues.”

Cities: Skylines © Colossal Order

A mod to remove Chirper was one of the first fan projects on the Workshop. But other mods are more ambitious. Korppoo singles out a flight simulator that a fan has modded into the game – essentially a camera control trick that you can use to buzz around over your urban planning masterpiece like you’re peering out the canopy of a jet (“it’s cool!” she says. “It really doesn’t do much for the game, but it’s fun to play.”). Still others get their probing fingers deep into the game’s innards and set themselves extra challenges by switching off systems designed to make things easier.

“There’s [a mod] that disables the teleportation mechanic that we have,” says Korppoo. “Some people felt that the game is too easy, because if a citizen in the city wants to travel somewhere and they get stuck for too long, they get teleported back to where they came from. This is just so that traffic doesn’t gridlock and people who are not so skilled with handling the traffic won’t get stuck immediately. But someone made a mod that disable this feature, so the ones who really want to play hardcore can do it.”

Cities: Skylines © Colossal Order

When we ask if these sorts of mods are an indication that Cities is too easy, it seems we’ve missed the point. Where SimCity has disasters like earthquakes and rampant fires that test your stewardship in a crisis, Cities is more forgiving by design. Sometimes a single building will burn down. Sometimes citizens will whine about rent. But unless you work very hard to undo your own hard work (people can’t drink sewage, it turns out), the city just sort of… ambles on without you.

“It is quite easy,” Korppoo agrees. “Then again, it has this kind of optional depth that scales with the player’s skill and how much they want to get into the game. Something that sandbox games need to do is to support many kinds of playing styles. Some people just want to slowly let the game play in the background and do something else while they’re playing it, and other people want to have these really intense half an hour sessions. So the game tries to cater to all these styles, so that different players – or even the same person on different days – can play it so that it’s fun… It’s more about self-exploration than ‘beating’ the game. So I would say that the game is quite easy, but that’s not the point of the game, to be challenging.

“I think it’s a good way to do it,” she continues. “My intuition says that the players who want the game to be hard might be the ones who actually know how to use mods and aren’t afraid to download and try them. So the people who really want to ‘beat’ the game, who want it to be really tough and challenging, they can adjust how hard the game is. That’s perfect… They can choose the mods they want, and get the experience they’re looking for.”

But investment in a modding scene is a costly business. As Hallikainen explains, building in mod support from day one can be a hard sell – particularly when it involves, as it did for Colossal Order, hiring a programmer full-time to build nothing but mod tools.

“Try and tell [most] publishers, ‘we need to have one guy work for an entire year on a feature that will not directly bring you any money,’ [and] that [could] be a little bit tricky,” she says. “What could this programmer have brought to the project if he had been working on the gameplay? You need to put the effort into it, and it’s a big task.”

Cities: Skylines © Colossal Order

One recent, and controversial, experiment on the Steam Workshop was to introduce the option for creators to charge for the mods they make. Skyrim was the first – and only – game to trot out the new business model, which was quickly chased back into its cave by a mob of angry fans wielding torches, pitchforks and equippable in-game protest placards with ‘No paid mods’ scrawled over them in MS Paint. Modding has, traditionally, always been unpaid work, and the result has been a surge in cooperative communities churning out free extra content ( some of it great , some of it awful) for games for years after release. But the question remains: is it wrong for people to want compensation for hard work?

“As a player, I would like to have these small payments to get extra content,” says Korppoo. “But as a developer, it’s really hard to get done decently. Because for us, we have [thousands of] mods. How could we test all of those?

“The idea behind [a system of paying for mods] is that it gives more options to the player, which is always good. It gives more options to the modders, but there are so many things that have to be really thought out. How can we make sure that the modders can’t steal other people’s creations and then sell those? How can we protect the copyrights? How do we make sure that the quality is high enough? It’s easy to assume that players will take care of it on their own, but to actually have that implemented in a way that is fair for the modders [and] for people downloading and paying for the mods. As we saw [with Skyrim], it didn’t exactly…

She pauses.

“Go as planned,” Hallikainen finishes.

It is the future [though],” says Korppoo. “I mean, sure, I think we should keep that option [of free mods]. We shouldn’t enforce [paid mods]. I think modding has always been… In a sense, the way modding is done, it’s kind of supposed to be free for the player. It’s supposed to be something fun that the modders do, but to give them the option so that modders get something out of the model…

“But... we have to make sure that when people are paying for the content that it actually matches the description. And I think the biggest issue is how we do this, as well as how we still make sure that the people who still want to do this for free [are still able to]. Because with the modding community, the whole point is that we do things together to make the game better, and it would be very sad to lose that.”

Cities: Skylines © Colossal Order

That close contact with its fanbase is already informing future releases for Skylines (in addition to the tunnels update that just launched, the next big thing that fans have asked for are European buildings, which the CO says will be along shortly). But it’s also, say the developers, helping to form the idea of the studio’s next project – though they won’t be pulled on the details.

“We are planning to start another game project sometime soon,” says Hallikainen. “We definitely want to focus on old-school simulator games and definitely PC. PC, Mac and Linux, those are our ‘thing’. But I think we’re maybe going to do something a little bit different. We’ve now made three games about cities, so I don’t know what the new project is, but I think we might do something a little bit different. We’ll see.

“But one thing at a time. We’re only 13 people so we have to finish [this game] first, and then see. Definitely for the modding community there’s new things coming, because we definitely want to support that as well. So there are improvements coming to the modding tools.

“Now I’m going to shut up because Paradox might say something to me. I’m going to be very cryptic about it.”