Microsoft Execution Containers vs SPACE

Microsoft Execution Containers

MXC puts nine operating-system sandbox backends behind one typed request, with network access denied by default and a JSON Schema for the stable 1.0.0 contract. Version 1.0.0 is two days old as of 8 October 2026. Enforcement varies by backend, and isolation_session cannot restrict networking at all.

SPACE

Once deployed, SPACE's native API has a public OpenAPI 3.1 contract, stable error codes with a retryable flag and 24-hour idempotency keys, and egress and credential controls sit outside the VM. A person must first deploy it on a Linux x86_64 host with KVM and Kubernetes. Version 0.8.0 has no tagged release, changelog or public container images.

Microsoft Execution Containers

1. Import from @microsoft/mxc-sdk/v1. The package root exports nothing.
2. Call getPlatformSupport() first and stop if isSupported is false. getAvailableBackends() is advisory and launch-time validation still applies.
3. Set network.egress.default to allow only when the task needs it. Omitted network policy resolves to deny in every direction.
4. Never pass --audit to an executor for untrusted code. It turns off all sandbox security for the workload.
5. Read ExecutionResult.warnings after each run. Security warnings arrive there and are not written to stdout or stderr.

SPACE

1. Ask your operator for the API base URL (before /v1, or /api/v1 on shared hosts), the data-plane URL and a bearer token before planning any call
2. Poll the returned operation until it succeeds and the sandbox is running before creating a command. A 202 response is not readiness
3. Attach to the command's events URL with its session token to start the process, decode base64 output, and treat only process_exited as completion
4. Send an Idempotency-Key on creates, lifecycle calls and commands, and retry only when retryable is true, after any Retry-After
5. Save output as it arrives. Reconnecting with Last-Event-ID returns resync_required, not the missed output