Namespace arm64 and macOS Runner Shapes: Choosing the Right Label

Namespace supports arm64 and macOS runners, but the valid label combinations differ by platform. Getting the shape right avoids an unschedulable job.

According to Namespace's runner-configuration docs, Namespace supports Linux amd64 and arm64, Windows, and macOS runners, but not every architecture and shape combination is valid on every platform. This guide covers the platform-specific rules so your runs-on label resolves to a real runner. Confirm the current shape list in Namespace's docs.

Architecture rules

Per Namespace's docs, Linux supports both amd64 and arm64, but arm64 is not available for Windows. Choosing arm64 on Windows produces an invalid label, which means the job will not schedule.

Linux and Windows shapes

According to Namespace's runner-configuration docs, standard Ubuntu and Windows shapes range from 2x4 (2 vCPU / 4 GB) up to 32x64 (32 vCPU / 64 GB). Build the label as nscloud-{os}-{arch}-{shape}, for example nscloud-ubuntu-24.04-arm64-16x32.

macOS shapes

Per Namespace's docs, macOS uses its own shapes (their reference lists options such as 6x14, 12x28, and 12x56) and supported macOS versions. macOS also carries a much higher pricing multiplier, so pick the smallest shape that meets your build's needs. Confirm the current macOS shape and version list in Namespace's docs.

Build a valid label

Pick the OS and a version Namespace supports (for example ubuntu-24.04).
Pick amd64 or arm64 (remember arm64 is not on Windows).
Pick a supported shape for that platform.
Assemble nscloud-{os}-{arch}-{shape} and use exactly one such label in runs-on.

Cost-aware runner choice

If reliability and per-minute cost are what you are optimizing for, Latchkey is a managed GitHub Actions runner with the same one-line runs-on swap that adds self-healing (transient and mechanical failures are detected, fixed, and retried automatically) at up to 58% lower per-minute cost than GitHub-hosted. You can pilot it on one workflow alongside Namespace and compare.

Frequently asked questions

Can I run arm64 on Windows with Namespace?

According to Namespace's runner-configuration docs, arm64 is not available for Windows. Use amd64 for Windows, or arm64 on Linux.

Where do these Namespace facts come from, and is the pricing current?

The Namespace details on this page are drawn from Namespace's own public pages, reviewed 2026-07-02: the product site (namespace.so), pricing (namespace.so/pricing), the GitHub Actions getting-started and runner-configuration docs (namespace.so/docs/solutions/github-actions and namespace.so/docs/reference/github-actions/runner-configuration), and the caching docs (namespace.so/docs/solutions/github-actions/caching). Vendor pricing and features change, so verify current Namespace pricing and shapes on namespace.so/pricing before you decide.