macOS 26 On Apple Silicon With Vimy + Viable

Use this on:

• Apple silicon Macs (arm64: M1 / M2 / M3 / M4)
• macOS 12+

Provider minimums from Viable help:

• Disk: 20 GB minimum
• Disk: 40 GB minimum if you want guest macOS updates
• Memory: 4 GB minimum
• Cores: 2 minimum

Working macOS 26 profile:

• Disk: 100 GB
• Memory: 4 GB
• Cores: about half of host cores

Fast path:

1. Install:

• Homebrew: https://brew.sh/
• Viable: https://formulae.brew.sh/cask/viable
• Vimy: https://formulae.brew.sh/cask/vimy

brew install --cask viable vimy

2. Open Viable.
3. Set: Virtual Disk = 100 GB Memory = 4 GB Cores = about half of your host cores
4. Click Download....

5. Save the VM bundle as a .vimi file on your chosen storage volume. Example: /Volumes/YourSSD/macos26-100gb-4gb-5cpu.vimi

6. Wait for Viable to show Installation succeeded.

7. Launch it with Vimy.

open -a Vimy /path/to/macos26-100gb-4gb-5cpu.vimi

8. If it worked, you should land on the macOS 26 setup Language screen.

Validated example:

• Host: macOS 26.3, Apple M4, 16 GB RAM, 10 CPU cores
• Guest: 100 GB / 4 GB / 5 cores

Can vary:

• VM name
• save path
• display
• network

ARM host note

This guide is for Apple silicon Macs using Apple's virtualization stack. It is not a guide for generic ARM PCs, Linux ARM hosts, or Windows on ARM.

Storage notes

External SSD, recommended:

• Pick the SSD in the Where dropdown in the Save dialog.
• Example path: /Volumes/YourSSD/macos26-100gb-4gb-5cpu.vimi
• This keeps the large VM files off the host disk.

Host disk, works if you have space:

• Save anywhere on the host, for example: ~/VMs/macos26-100gb-4gb-5cpu.vimi
• Keep plenty of free space available on the host volume.

Prompt for Codex or Claude Code

Paste this into Codex or Claude Code.

Help me set up macOS 26 on this Apple silicon Mac using Viable and Vimy.

Before doing anything:
1. Check the host first:
   - macOS version
   - Apple silicon chip
   - total RAM
   - total CPU cores
   - free disk space
2. Do not start immediately.
3. First reply with:
   - a short host summary
   - the Viable minimums
   - your recommended VM settings for this machine
4. If I already gave preferences, use them.
5. If I did not give preferences, recommend a sensible default profile first, then ask whether I want any changes to:
   - save location: host disk or external SSD
   - VM name
   - disk size
   - RAM
   - CPU cores
6. Keep recommendations practical and brief.
7. Wait for explicit confirmation from me like "okay good" before starting.

Use these Viable minimums:
- disk: 20 GB minimum
- disk: 40 GB minimum if guest macOS updates matter
- memory: 4 GB minimum
- cores: 2 minimum

Use this as the safe default profile unless host limits suggest otherwise:
- disk: 100 GB
- memory: 4 GB
- cores: about half of host CPU cores

When I confirm, then:
1. Install what is missing.
2. Install Viable and Vimy with Homebrew.
3. Create the VM as a .vimi bundle.
4. Save the bundle to the storage location I chose.
5. Wait for Viable to say "Installation succeeded."
6. Launch it with Vimy.
7. Verify the VM reaches the macOS setup screen.

Troubleshooting / things to watch for:
- 2 GB RAM was not enough in a failed attempt.
- 20 GB disk was also a bad choice for this workflow.
- A working run used 100 GB disk, 4 GB RAM, and about half the host cores.
- Viable's Save dialog can default to the host home folder, so verify the target volume before saving.
- If install fails, read Viable's status text and check system logs for Apple virtualization / AMRestore errors.
- One failed run showed AMRestoreErrorDomain code 100 and messages like "Failed to locate restore SEP firmware".
- Do not trust a black Vimy window by itself; first confirm Viable actually said "Installation succeeded."
- If Vimy opens but only shows a black screen, capture the VM window directly and verify whether setup UI ever appears.
- If publishing docs or screenshots afterward, check for personal info in screenshots before pushing public.
- If anything fails, tell me exactly which step failed, what you observed, and the next best retry.

Keep updates short and practical while you work.