ConceptsTemplates

Templates

Define repeatable sandbox baselines without baking project state or reusable secrets into the environment.

A template is a reusable definition for creating a Jio sandbox. It captures the environment that should be consistent across runs while leaving task-specific state to the sandbox and session.

Templates make replacement practical. When a sandbox becomes difficult to understand, you can preserve the intended project changes and recreate the environment from a known baseline.

What a template should define

  • base operating system or machine image;
  • language runtimes and build tools;
  • system packages and trusted setup scripts;
  • default resource and network policy;
  • filesystem layout and workspace identity;
  • health checks used before a session connects.

What stays out

Do not treat a template as a snapshot of everything on a working machine. Keep these inputs separate:

Keep outside the templateSupply at creation or session time
Long-lived credentialsTask-scoped secrets
A developer's home directoryThe project checkout or artifact
Mutable dependency cachesA controlled cache mount or restore step
Session historyCurrent connection and approval context

Template lifecycle

Define

Describe the minimum trusted baseline required by a class of workloads.

Version

Give material changes a new version so existing sandboxes remain explainable.

Instantiate

Create a sandbox, apply policy, and run health checks before an agent connects.

Replace

Recreate sandboxes from a newer or known-good template instead of repairing unexplained state indefinitely.

Templates improve repeatability, not trust by themselves

A template can still contain vulnerable packages or unsafe defaults. Review its source, provenance, and policy before using it for unfamiliar code.

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