I am the lead developer on a multiplayer survival game named Rust. Last week, we made a change to the game that upset a lot of people: we made half of our players, picked at random, play as women. We also made some of them black. The response has been extreme.

Rust is not a game about identity. The objective in Rust is to survive. This is made difficult by things such as starvation, dehydration, radiation, exposure and bear attacks. The biggest threat in the game comes from other players who are trying to survive in the same conditions. You will survive better if you’re a part of a group, but this takes a lot of mutual trust. If you kill someone you’ll be able to loot their corpse and take all their food, medicine and weapons. This makes the game very interesting socially, since players struggle with trust and slowly build up relationships with one another.

The game is in “early access”, which means it’s in active development and we update it every week. Despite this, it has sold over 3.5m copies since it was first released in 2013, and around half a million people play every week. Whenever a project has this kind of popularity, people become very passionate. But the range and strength of opinions have never been this intense.

Originally every player appeared in game as a white bald guy. We were still in the early stages of development and had other things to focus on. Recently, though, we decided to change this. We decided that we didn’t want players to pick their own appearance. We felt that player customisation had got a bit out of control in other games. And we didn’t want to spend six months making a player customisation tool – we wanted to concentrate on the game. We also wanted the appearance of the players to be consistent over time. A survivor shouldn’t be able to attack another then come back later with a different gender or race and befriend the same player. They should be recognisable consistently and long-term – so anyone likely to commit a crime would be more likely to wear a balaclava or a face mask.

So this is what we did. Gender and race are randomly selected and linked to a player’s account, permanently unchangeable.

Inevitably, there are people who like it and people who don’t. Some players have praised what we’re doing. Like us, they think that who you are in the game, your race and gender, makes no difference to the actual gameplay – and are happy to have the diversity. Others aren’t so positive. They feel that playing a gender or race that doesn’t match their own is detrimental to their enjoyment.

For race, this seems to be a regional thing. For example, most complaints about being black in the game have generally been from Russian players. With gender it seems to be more of a geography-free complaint.

Here’s one of the many messages we’ve received from disgruntled male players: “Why won’t you give the player base an option to choose their gender? I just want to play the game and have a connection to the character like most other games I play. Not have some political movement shoved down my throat because you make the connection we can’t choose our gender in reality so let’s make it like that in game too.”

Others have accused us of forcing them to accept our “feminist ideals”. Some have told us that they are quitting the game entirely. One called the move the dumbest thing we’ve ever done.

Our female players seem more pragmatic. They point out that they’ve already being play Rust as men for the past two years. Some have got in touch to thank us. Mostly they see it as no big deal.

We’ve also received complaints from transgender players. One called the new system horrifying, unpleasant and uncomfortable. Another argued that assigning a fixed sex was reminiscent of real-world transphobia.

It’s maybe understandable why some male gamers wouldn’t want to play as women. They’re just not used to being forced to. You could probably count on your fingers the number of major, big-budget games where you have no choice but to play as a woman, never mind having no choice but to play as a black woman. Female gamers are obviously more forgiving – they’ve been playing games as men for most of their lives.

I understand the arguments from transgender players – well, as much as a straight man can. But it feels to me like the same response stands. We’re assigning gender randomly in game – not in real life.

Ultimately the decision comes down to gameplay. We don’t believe that letting you choose your race and gender would improve the game. On the other hand, randomising everyone’s gender and race meets all our requirements. We get an even spread of races and genders that make players more identifiable – while at the same time making the social aspects of the game much more interesting.