# Juju > Juju is an open source orchestration engine for deploying, integrating, and managing applications across Kubernetes, VMs, and bare metal using software operators called charms. 2026 CC-BY-SA, Canonical Ltd. ## Pages in this subsection - [Constraint](https://documentation.ubuntu.com/juju/3.6/reference/constraint.md): Juju constraints reference: customize compute resources with specifications for CPU, memory, storage, networking, and instance types. ## Optional - [Top-level llms.txt](https://documentation.ubuntu.com/juju/3.6/llms.txt): Complete documentation index.