So that game developers don't have to rebuild all the rules for their game universes for every game, they use Unity which is one of several products that offers pre-built frameworks to build their games on top of.

This offers several advantages, the main ones being:

1. You don't reinvent the wheel or the physics for angular momentum for every game, so development time is massively reduced.
2. You only develop your game once, but can compile it for use on many platforms. So a single developer can be writing code that can be used for the PC, Play Station, XBox and so on.
3. Skills learned in one game's development transfer to quicker development in your next game.

The way that Unity were paid historically was that you paid a subscription for each developer that was using it to write your game. There were several tiers of subscription, that met the needs of developers in small indies right through to huge multinationals.

It didn't matter how well your game sold, your cost was limited to the subscriptions you paid for. And you released your game bundled with the framework's 'run-time' from Unity that supported your in-game universe.

This changed recently when the executives at Unity had the spiffing idea of charging 20 US cents per installation of the run-time too, while also killing off the cheapest tier of the model subscription.

This meant that the indies suddenly have to pay more for each subscription, and they get to pay a fee for every installation of their game - not every sale - every installation. So every pirated copy - extra charge, every second install on the Steam Deck - extra charge...

What extra has Unity done to deserve the extra cash? In a nutshell - nothing. They just decided to unilaterally change their terms and take a bigger chunk of the pie for doing nothing more at the expense of the customers making the mistake of building on top of their product and being tied into their ecosystem.

As an analogy, imagine buying a season ticket to travel on the train to work each day, you pay €200/month for unlimited travel between the station closest to home and closest to work. This carries on for several years, and then suddenly the rail operator announces a 'communal rolling stock fee', every time you use your ticket there's a €1/passenger fee for each passenger boarding the same train as you whenever you travel! The more busy the train, the bigger the amount you have to pay!

What was a fixed monthly fee could be anything, you have no way to budget the cost, and you have to trust the same people screwing you to get the count right each time with no way of being certain they got it right...

What extra work is the rail operator doing, nothing they are just charging more for the same service.

And what did you do to deserve this? Nothing you just trusted the company you were dealing with to remain reasonable, and not invent bullshit charges.

Back to Unity...

As a result a lot of developers in late stage development plan to switch to a competitor for their next game. Those in early stages are looking at starting over. And there have been reports of publishers walking away from deals with developers because of the unknown risks of a new game because it was developed using Unity.

The easily predictable end result: many if not all of Unity's customers are vocally incandescent with justified rage.

TLDR: Software library company got greedy; they shat in the pool and tried to charge their customers a 'poop in the pool' fee, and every last one of their customers is very (very) loudly incredulous at such ass-hattery.

From what I understand it is a popular game engine many developers have used in their games, and are still developing games with. This happened under a regular licensing agreement, which usually means a fixed sum or something tied to sales.

Now unity had the benighted idea to unilaterally add an additional charge to this, billing the developers for each and every installation of their game, which is not only incredibly greedy but also short sighted and ignorant of many common cases that would inflate those numbers (reinstallation for any reason being one of them).

Naturally developers affected by this are quite upset and are considering possible solutions to this self inflicted hostage situation.

Unity is a game engine and a bunch of ancillary services, analytics and tracking and what not. It's been free to use and publish games with as long as your company revenue was under a certain amount. Over that amount and you'd have to buy a license for I think about $1600 a year.

The brouhaha was because they changed their income model to charge people/companies who create their game using the unity engine to make games on a per install basis. Up to 20cents per install of your game ( but only if your revenue was over $200k AND installs was over 200k, raising to $1m AND 1m installs with the unity pro license) .

The changes would take place next January leaving developers with very little time to make any changes to their revenue model. Unity (the company) also changed the terms of use of Unity (the game engine software) so that it was retroactive across all previous versions of unity, ie. If you didn't like the new terms you couldn't just carry on using an older version of it.

If you were being charitable you'd call it a clumsy launch or even ill considered. But it went down like a bucket of cold sick with the game dev' community who viewed it like a greedy shakedown.

Unity is a game engine used by a lot of developers, many of them indies. Some popular games that use Unity are Among Us, Cuphead, Cult of the Lamb, and Tunic. They recently made several changes to their TOS that has upset the gaming community.

Unity used to have a clause in the TOS stating:

"if the Updated Terms adversely impact your rights, you may elect to continue to use any current-year versions of the Unity Software (e.g., 2018.x and 2018.y and any Long Term Supported (LTS) versions for that current-year release) according to the terms that applied just prior to the Updated Terms (the “Prior Terms”)"

This meant that if you didn't agree with the new terms, you could continue using a different version of Unity and the new terms wouldn't apply to you. In April 2023, they removed that clause completely. A week ago, they announced new terms: every game install will be charged a fee of up to $0.20 starting next year, depending on what Unity subscription the developers have and how much revenue/installs the game receives.

This change was set to cover all existing Unity games, even ones made on older versions. Any time anyone installed the game, even if they had installed it previously, the developer would be charged a fee. Many of the games made with Unity are under $20, with some of the popular ones being $5 or less. Immediately people thought of ways this could be trouble: Scripts to install the same game over and over, people sharing their game libraries with family/friends, those with multiple computers/laptops/tablets.

Unity announced on Sep 17, 2023 that they would not be going forward with this new policy:

We have heard you. We apologize for the confusion and angst the runtime fee policy we announced on Tuesday caused. We are listening, talking to our team members, community, customers, and partners, and will be making changes to the policy. We will share an update in a couple of days. Thank you for your honest and critical feedback.

It's unclear what Unity will do now. Many developers have started looking at an alternative called Godot, and some even plan on canceling their Unity subscription because they have lost faith in the company.

Unity is a tool that game developers use to build games. You don't have to use Unity, but lots of really popular games use it and it makes development easier. Recently, the company behind Unity (also called Unity) decided to add an extra fee for using Unity. That would have been bad enough, but Unity went with adding a fee in which the game developers need to pay every single time a customer installs their game.

This was a startlingly bad idea, because you end up punishing games that sell well. But it also opens up entire cans of worms, because trolls could easily mess with developers by simply buying a game, then installing, uninstalling, then reinstalling again and again. And because the fee is applied per install, a single troll could easily build up massive fees for the developers. On top of that, this new fee is applied retroactively to all games that were built with Unity. So it doesn't matter if you built your game 10 years ago - you'll still get charged if a user installs your game.

In response, many developers are pushing to boycott Unity, with many saying that they would go bankrupt with the new fees. It also came to light that many of the top executives at Unity sold a large number of their shares in the company shortly before making the announcement of the new fee, showing that the top executives knew that the fee would be unpopular but went with it anyways. It also brought up the concern that they were engaging in insider trading, which is illegal.