# Proposal to Deprecate macOS Intel Support in ITK 6 (Retain in ITK 5)

**URL:** <https://discourse.itk.org/t/proposal-to-deprecate-macos-intel-support-in-itk-6-retain-in-itk-5/7510>\
**Category:** Engineering\
**Tags:** macos\
**Created:** [April 25, 2025, 9:19pm UTC](https://discourse.itk.org/t/proposal-to-deprecate-macos-intel-support-in-itk-6-retain-in-itk-5/7510 "2025-04-25T21:19:51Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![matt.mccormick](https://discourse.itk.org/user_avatar/discourse.itk.org/matt.mccormick/32/7_2.png) [@matt.mccormick](https://discourse.itk.org/u/matt.mccormick)\
**Post date:** [April 25, 2025, 9:19pm UTC](https://discourse.itk.org/t/proposal-to-deprecate-macos-intel-support-in-itk-6-retain-in-itk-5/7510/1 "2025-04-25T21:19:51Z")

</div>

### **Proposal**

Deprecate macOS Intel (x86\_64) support in ITK 6, while maintaining it in ITK 5 as a long-term support (LTS) release. This aligns with Apple’s phased sunsetting of Intel Macs and industry-wide shifts toward Apple Silicon optimization.

* * *

### **Rationale**

**1. Apple’s Official Transition Timeline**

- Apple completed its transition to Apple Silicon in June 2023 with the Intel Mac Pro’s discontinuation\[1\].
- macOS 17 (2026) is projected to be Apple Silicon–only, ending major OS updates for Intel Macs\[2\]\[3\].
- Security updates for Intel Macs will continue until ~2027 for newer models (e.g., 2019 iMac, Mac Pro) but lack feature parity\[2:1\]\[4\].

**2. Third-Party Software Trends**

- Major developers (e.g., Adobe, Microsoft) now prioritize Apple Silicon optimizations, with some dropping Intel support entirely\[2:2\]\[4:1\].
- ARM64 macOS now dominates developer toolchains, with Xcode and CI/CD pipelines increasingly excluding Intel\[4:2\].

**3. ITK Maintenance Burden**

- Supporting legacy Intel macOS complicates builds, testing, and CI/CD for ARM64-specific optimizations.
- macOS Intel GitHub Action Runners (`macos-13`) are slower than the ARM counterparts.
- Deprecating Intel in ITK 6 allows focused resources on Apple Silicon performance.

* * *

### **Proposed Implementation**

- **ITK 6** :
  - Remove Intel macOS from build matrices.
  - Document deprecation in release notes, directing users to ITK 5 for legacy workflows.

- **ITK 5** :
  - Maintain Intel macOS support as an LTS branch until 2027 (aligned with Apple’s security update window).
  - Backport critical fixes only.

* * *

### **Community Impact Considerations**

- **Affected Users** : Researchers/clinicians relying on older Intel Macs for specialized hardware (e.g., GPUs, PCIe devices).
- **Mitigation** : Provide migration guides for Apple Silicon or Linux/Windows alternatives.
- **Timeline** : Target deprecation for ITK 6.0 (Q1 2026), coinciding with macOS 17’s expected release\[3:1\].

* * *

### **Supporting Data**

| Key Fact | Source |
| --- | --- |
| macOS 17 (2026) likely Apple Silicon–only | \[2:3\]\[3:2\] |
| Final Intel Mac (Mac Pro) discontinued June 2023 | \[1:1\] |
| Security updates until ~2027 for newer Intel Macs | \[2:4\]\[4:3\] |
| Average 2-year security update window post-OS EOL | \[2:5\]\[3:3\]\[4:4\] |

* * *

### **Request for Feedback**

Please share:

1. Use cases requiring Intel macOS support beyond 2026.
2. Concerns about legacy hardware/software dependencies.
3. Preferences for LTS backport policies in ITK 5.

_References inline via linked sources. Data current as of April 2025._

* * *

1. [Mac transition to Apple silicon - Wikipedia](https://en.wikipedia.org/wiki/Mac_transition_to_Apple_silicon)

2. [Got an Intel Mac? Here's the deal so far, and possible future](https://9to5mac.com/2024/06/19/got-an-intel-mac-future/)

3. [When will Apple stop supporting Intel Macs? - 9to5Mac](https://9to5mac.com/apple-intel-mac-support/)

4. [How Long Will Intel Macs Be Supported? - ComputerCity](https://computercity.com/desktops/mac/how-long-will-intel-macs-be-supported)

---

<div class="post-metadata">

**Author:** ![dzenanz](https://discourse.itk.org/user_avatar/discourse.itk.org/dzenanz/32/1093_2.png) [@dzenanz](https://discourse.itk.org/u/dzenanz)\
**Post date:** [April 28, 2025, 1:32pm UTC](https://discourse.itk.org/t/proposal-to-deprecate-macos-intel-support-in-itk-6-retain-in-itk-5/7510/2 "2025-04-28T13:32:52Z")

</div>

The discussion has started on GitHub:

> <https://github.com/InsightSoftwareConsortium/ITK/issues/5326>
>
> \### \*\*Proposal\*\*
> 
> Deprecate macOS Intel (x86\_64) support in ITK 6, while maintai…ning it in ITK 5 as a long-term support (LTS) release. This aligns with Apple’s phased sunsetting of Intel Macs and industry-wide shifts toward Apple Silicon optimization.
> 
> \---
> 
> \### \*\*Rationale\*\*
> 
> \*\*1. Apple’s Official Transition Timeline\*\*
> 
> \- Apple completed its transition to Apple Silicon in June 2023 with the Intel Mac Pro’s discontinuation\[^4\].
> \- macOS 17 (2026) is projected to be Apple Silicon–only, ending major OS updates for Intel Macs\[^2\]\[^3\].
> \- Security updates for Intel Macs will continue until ~2027 for newer models (e.g., 2019 iMac, Mac Pro) but lack feature parity\[^2\]\[^5\].
> 
> \*\*2. Third-Party Software Trends\*\*
> 
> \- Major developers (e.g., Adobe, Microsoft) now prioritize Apple Silicon optimizations, with some dropping Intel support entirely\[^2\]\[^5\].
> \- ARM64 macOS now dominates developer toolchains, with Xcode and CI/CD pipelines increasingly excluding Intel\[^5\].
> 
> \*\*3. ITK Maintenance Burden\*\*
> 
> \- Supporting legacy Intel macOS complicates builds, testing, and CI/CD for ARM64-specific optimizations.
> \- macOS Intel GitHub Action Runners (\`macos-13\`) are slower than the ARM counterparts.
> \- Deprecating Intel in ITK 6 allows focused resources on Apple Silicon performance.
> 
> \---
> 
> \### \*\*Proposed Implementation\*\*
> 
> \- \*\*ITK 6\*\*:
> - Remove Intel macOS from build matrices.
> - Document deprecation in release notes, directing users to ITK 5 for legacy workflows.
> \- \*\*ITK 5\*\*:
> - Maintain Intel macOS support as an LTS branch until 2027 (aligned with Apple’s security update window).
> - Backport critical fixes only.
> 
> \---
> 
> \### \*\*Community Impact Considerations\*\*
> 
> \- \*\*Affected Users\*\*: Researchers/clinicians relying on older Intel Macs for specialized hardware (e.g., GPUs, PCIe devices).
> \- \*\*Mitigation\*\*: Provide migration guides for Apple Silicon or Linux/Windows alternatives.
> \- \*\*Timeline\*\*: Target deprecation for ITK 6.0 (Q1 2026), coinciding with macOS 17’s expected release\[^3\].
> 
> \---
> 
> \### \*\*Supporting Data\*\*
> 
> | Key Fact | Source |
> | :-- | :-- |
> | macOS 17 (2026) likely Apple Silicon–only | \[^2\]\[^3\] |
> | Final Intel Mac (Mac Pro) discontinued June 2023 | \[^4\] |
> | Security updates until ~2027 for newer Intel Macs | \[^2\]\[^5\] |
> | Average 2-year security update window post-OS EOL | \[^2\]\[^3\]\[^5\] |
> 
> 
> \---
> 
> \### \*\*Request for Feedback\*\*
> 
> Please share:
> 
> 1. Use cases requiring Intel macOS support beyond 2026.
> 2. Concerns about legacy hardware/software dependencies.
> 3. Preferences for LTS backport policies in ITK 5.
> 
> \*References inline via linked sources. Data current as of April 2025.\*
> 
> \[^1\]: https://www.reddit.com/r/MacOS/comments/18dt837/how\_much\_longer\_for\_intel\_macs\_lets\_hear/
> 
> \[^2\]: https://9to5mac.com/2024/06/19/got-an-intel-mac-future/
> 
> \[^3\]: https://9to5mac.com/apple-intel-mac-support/
> 
> \[^4\]: https://en.wikipedia.org/wiki/Mac\_transition\_to\_Apple\_silicon
> 
> \[^5\]: https://computercity.com/desktops/mac/how-long-will-intel-macs-be-supported
> 
> \[^6\]: https://discussions.apple.com/thread/255950497
> 
> \[^7\]: https://forums.macrumors.com/threads/rules-for-mac-os-dropping-hardware-support-and-for-retiring-mac-oss.2415471/
> 
> \[^8\]: https://www.pcmag.com/news/how-long-can-you-keep-using-an-intel-mac
> 
> \[^9\]: https://discussions.apple.com/thread/254657045
> 
> \[^10\]: https://www.refurb.me/blog/are-intel-macs-obsolete
> 
> \[^11\]: https://eclecticlight.co/2024/08/06/how-long-does-apple-support-mac-firmware/
> 
> \[^12\]: https://news.ycombinator.com/item?id=41176265
> 
> \[^13\]: https://en.wikipedia.org/wiki/MacOS\_version\_history
> 
> \[^14\]: https://en.wikipedia.org/wiki/Apple\_silicon
> 
> \[^15\]: https://www.reddit.com/r/mac/comments/1g93ctg/macos\_16\_is\_going\_to\_drop\_support\_for\_all\_intel/
> 
> \[^16\]: https://discussions.apple.com/thread/8415153
> 
> \[^17\]: https://endoflife.date/macos
> 
> \[^18\]: https://9to5mac.com/2022/12/15/apple-silicon-transition-timeline-mac-pro/
> 
> \[^19\]: https://support.apple.com/en-us/100100
> 
> \[^20\]: https://forums.macrumors.com/threads/will-macos-15-drop-support-for-intel.2421008/