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macOS Big Sur: The New Rosetta 2

An Important feature no one is talking about

“Huge leap forward for the Mac”

With Apple’s Silicon, the upcoming Mac lineup will use arm64 architecture. Whereas the older Macs with Intel-based processors used x86–64 architecture. With this transition, Mac devices will be able to run apps made for iOS and iPadOS without any change to the code.

However, because of this transition from x86–64 to arm based architecture, apps made for Intel-based Mac devices won’t be able to run on newer arm based devices. That’s where Rosetta 2 comes. With macOS Big Sur(OS 11), Apple announced Rosetta 2 to ensure these apps to work on newer devices without any hiccup.

So what exactly is this Rosetta 2?

Rosetta 2

Rosetta is a translation process that allows users to run apps that contain x86–64 instructions on Apple silicon. Rosetta is meant to ease the transition to Apple silicon, giving developers time to create a universal binary for their app. It is not a substitute for creating a native version of your app.

The transition to Apple silicon in the Mac will create a common architecture across all Apple products, making it easier for developers to write and optimize programs and applications for the entire Apple ecosystem.

With Rosetta 2, developers can make their iOS and iPadOS apps available on the Mac without any modifications. Developers will be able to easily create a single app for the new Macs with Apple silicon, while still supporting Intel-based Macs.

OG Rosetta Vs. Rosetta 2

Apple released the original Rosetta in 2006 to facilitate Apple’s transition from PowerPC to Intel. It allowed many PowerPC applications to run on certain Intel-based Mac computers without modification. There was a downside with the OG Rosetta, programs that ran on the intel powered Mac devices ran comparatively slower. This happened due to the technological limitations of the OG Rosetta. The translator was only able to interpret the code in real-time.

Whereas Rosetta 2 can convert an application right at installation time, effectively creating an arm-optimized version of the app before you’ve opened it. Apple claims the end-user won’t even be able to notice the existence of Rosetta.

Not a long-term Solution

Rosetta 2 is not a long term solution. It is just a temporary solution for developers to make their existing Intel-based programs to run on arm-based Mac devices. Apple is urging developers to create native apps for their arm-based Macs. Apple ended the support for OG rosetta only after 3 years of its release.

Apple made available a Developer Transition Kit to aid the developers to create native apps. The Developer Transition Kit consists of a Mac mini with Apple’s A12Z Bionic SoC inside and desktop specs, including 16GB of memory, a 512GB SSD, and a variety of Mac I/O ports. After the end of the transition program, the developers must return the kit to Apple.

Geekbench results uploaded so far suggest that the A12Z-based Mac mini running through Rosetta 2 has average single-core and multi-core scores of 811 and 2,781 respectively. Apple slightly underclocked the A12Z processor in the kit to 2.4GHz. In comparison, iPad Pro running the same A12Z processor performed way better in Geekbench results which ran at 2.5GHz.

The transition kit was only made available to help the developers to run and test their programs. The Geekbench results uploaded so far won’t reflect the actual performance of the future Apple Silicon.


Rosetta 2 won’t be able to translate Kernel extensions and Virtual Machine apps that virtualize x86–64 computer platform. Because of this Windows virtualization software won’t be functional after the release of the arm-based Macs later this year.

Also, Boot Camp will no longer be available for use on Macs powered by Apple silicon. Macs will not be able to access the feature and Apple has not announced any replacement for it either. Microsoft even made it clear that it only licenses arm-based Windows 10 to manufacturers. No more Windows on Macs.

The Takeaway

Rosetta 2 will make the process of purchasing a new Mac seamless for end-users. It will avoid the problems that Microsoft faced during their arm transition process. Apple never announced whether its Apple silicon will be able to handle the graphic intensive processes like their older intel based devices nor did they announce anything about GPUs in their future lineup. They didn’t even announce how long will they be supporting older Intel-based Macs. Though the performance of the arm-based Apple silicon is still in the air. ARM processors are known for their better battery life and better connectivity than Intel-based processors.

What are your thoughts on Apple’s transition to arm-based silicon? Are you happy about it?

Written by

An Introvert, a YouTuber, a nerd, and a gamer. Writing about technology, science, and games.

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