#378  17th October 2025

Rosetta: Planning ahead

There was a discussion on installing Rosetta in the Setup Manager channel on the Mac Admins Slack this week. (Actually, it was about getting an icon for Rosetta, but I digress). This reminded me that sometime earlier this year, I realized that all the software in my testing environment was available as a universal or Apple silicon app. That means I could remove the 'Install Rosetta' step from my enrollment workflow.

I am very well aware that most deployments are far more complex than my testing environment, but I also checked my production MacBook and only found two Intel apps: iBooks Author, which was discontinued a few years ago, but it still works and I keep it around because I have not yet converted all of my iBooks documents to Pages. The other one is the Sonos app.

As Mac Admins, we've gotten so used to reflexively installing Rosetta, that we stopped thinking about it. Admittedly, it isn't hard and doesn't take up much time or bandwidth, so why bother?

Untypically, Apple has given us a roadmap. macOS Tahoe is the last version of macOS to support (some) Intel Macs. macOS 27 will be the last version of macOS with general Rosetta support. Intel-only binaries will stop working with macOS 28, expected to release in late 2027.

Now is the time to assess which of your organization's software still requires Rosetta, i.e. which of your software does not come in Universal or Apple silicon binaries yet. An easy way to determine this is to go to the Software > Applications area in the System Report app. Or use this command:

system_profiler SPApplicationsDataType -json | jq '.SPApplicationsDataType[] | select(.arch_kind=="arch_i64") | ._name'

(Replace the final ._name with .path (no underscore) to see where the app is located.)

For command line tools, you can use the file command:

$ file /usr/local/bin/desktoppr
/usr/local/bin/desktoppr: Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit executable x86_64] [arm64:Mach-O 64-bit executable arm64]
/usr/local/bin/desktoppr (for architecture x86_64): Mach-O 64-bit executable x86_64
/usr/local/bin/desktoppr (for architecture arm64):  Mach-O 64-bit executable arm64

To check an entire directory:

find /usr/local/bin/ -perm +111 \! -type d -exec file {} \;

(This will list all executables in /usr/local/bin which is where a lot of custom command line tools will be stored, but there might be more places that you need to check. The binaries that have only a single line with the x86_64 architecture are Intel only.)

We are now five years into the transition and any Intel-only apps or tools you identify are unlikely to have supportive or even responsive vendors. You will need time to communicate with the vendor and see if they will release an update. Otherwise, you and the users of the app will need the time to figure out alternative software or solutions. Planning ahead now might avert a crisis, two years from now, when the first Macs that will only run macOS 28 are going to ship.

In other update news, Apple released the third round of betas for the 26.1 updates this week. Should Apple follow their release schedules from previous years, I expect release candidates next week and the release a week later.