#Testlab backend requirements| Backend | Requirement ||---|---|| docker | images must contain `sleep` and `sh` (distroless unsupported — use vmlab) || vmlab | templates must ship the QEMU guest agent; each group gets a throwaway one-VM lab || vmlab (Windows scenarios) | guests must be Server 2019 / Windows 10 or newer |##Related-[docker backend](../references/entity_docker_backend.md)-[vmlab backend](../references/entity_vmlab_backend.md)-[Scenarios](../references/concept_scenarios.md)[← Back to SKILL.md](../SKILL.md)