Boxer

Developer diary: plans and progress reports.

Bump Saturday 7th January 2012

Boxer 1.3.1 is out now at a browser near you! Release notes are here: I’m afraid this update comprises boring old bugfixes and minor tweaks, with no new features to delight and astound.

1.3.1 is mainly intended as an end-of-life update for users still stuck on Leopard; bye guys! Boxer 1.4 will be along later this month, with a brand-new shader-based renderer and retina display support, ready for OS X 10.8 – and you’ll need Snow Leopard or newer to run it. (Yes, for really reals this time.)

This is why we can't have nice things

It's been a long time since I last talked about putting Boxer in the Mac App Store. The landscape has changed significantly since then, and Apple’s current policies mean that Boxer’s probably not coming to the App Store – not until the development climate changes, for the worse or for the better.

The main thing is that as of the start of June, all apps submitted to the App Store must now run in a restrictive sandbox environment that curtails the kinds of things an app can do and removes access to certain OS features altogether.

If you follow other Mac developers, you’ve likely read a lot of rants about the ramifications of the sandbox and the kind of things it prevents apps from doing. Here are all the ways (that I know of) that the App Store would affect Boxer:


App Store apps can only access files that are within the app’s own sandboxed filesystem (which is hidden from the user) or to which the user has implicitly granted them access: this by either opening files directly with the application, or by choosing them from a file-picker, or by drag-dropping them into the application.

This restriction would mean:


App Store apps can no longer open other apps directly, or talk to them via Applescript. This restriction would mean:


App Store apps cannot intercept and handle system-level key events. This restriction would mean:


App Store apps are not permitted to create or download other apps. This restriction would thwart my future plans to make gameboxes into first-class applications of their own.

This proviso is clearly intended to keep out alternative app stores like Steam and Bodega.


App Store apps are not permitted to download or support additional executable code, i.e. plugins. I have no plans to offer traditional plugins for Boxer, but it's debatable as to what actually constitutes a plugin: e.g. whether MT-32 ROMs or additional OpenGL shaders would be counted as plugins by Apple’s fickle review staff.


A case can be made that the Mac App Store terms of use are incompatible with the Grand Ole GPL, which opens Boxer up to being pulled from the App Store on spurious legal grounds. This threat has already been realised on the iOS App Store, where some GPL-licensed apps have been unceremoniously pulled after DMCA complaints from parties with axes to grind.


Compared to some apps, Boxer gets off lightly, and none of these restrictions on their own are dealbreakers for running DOS games: but they would put a dent in Boxer’s ease-of-use, and curtail future development angles, without offering me anything in return besides the increased exposure. Given that I don’t make any money off Boxer, the exposure would bring me no benefit (beyond basking in the glory of more happy users) and it would come with a much bigger support burden attached. Apple's mercurial policy changes would also leave Boxer at the risk of losing further features just to stay in the store once it’s there, or of being pulled from the store altogether at the whims of other people.

Closing remarks

It’s very late in the lifespan of an operating system to attempt to lock it down like this, and I’ve heard it likened to putting the genie back into the bottle. Some apps are simply unable to function within the sandbox, and so there has been a miniature exodus of app developers from the App Store since the new rules went into effect. Some high-quality apps, ironically including apps that Apple themselves have promoted, are now laying fallow in the App Store without the opportunity to submit new updates, and many other popular apps will now never be able to join the App Store. It’s possible that Apple will expand the sandbox API at a later point to let some of them back in, but I don’t have my hopes up.

Fortunately Apple seem to be in no hurry to remove your Mac’s ability to run well-behaved software from outside the App Store; they’ve made moves in OS X 10.8 to codify a distinction between unapproved apps that are made by any old rabble, and apps by trusted developers that just could not be distributed in the App Store for whatever reason. This indicates they recognise the ecosystem outside their App Store is still vital to the platform; let’s hope they keep thinking that way.

So there we go! For now Boxer will stay out of the App Store: until Apple expands the range of things possible in the App Store sandbox, or until Boxer evolves to a point where those restrictions are no longer relevant, or until Apple force my hand by preventing 3rd-party apps from running on OS X at all.

Design by 40watt.