E2B vs SPACE

E2B

Firecracker microVM with its own kernel per sandbox. Two major incidents over an hour in September 2026, on sandbox creation and on creating from snapshots.

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.

E2B

1. Set a timeout when you create a sandbox. The default is 5 minutes
2. Pause rather than kill when you'll come back. Resume takes about a second and nothing is billed while paused
3. Use Secret.fill in network transforms instead of passing API keys into the sandbox environment
4. Pace sandbox creation. Hobby allows 1 a second and 20 running at once
5. Move to the v2 sandbox endpoints. SDK 2.51.0 and later use them by default

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