> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stackshift.cloud/llms.txt
> Use this file to discover all available pages before exploring further.

# Updating template-backed stacks

> Preview diffs, resolve missing inputs, and apply the latest published template version safely.

<Tip>
  **Live.** This area is documented as current, user-reliable behavior.
</Tip>

## Goal

Use the template lifecycle path instead of treating updates as blind redeploys.

## Prerequisites

* A template-backed stack
* A newer published template version

## Workflow

<Steps>
  <Step>
    Open the update panel on the stack detail page.
  </Step>

  <Step>
    Review the preview, diff, and missing-input checks.
  </Step>

  <Step>
    Apply the update and watch the resulting release and recovery state.
  </Step>
</Steps>

## Preview before you apply

The update panel on the stack detail page previews the upgrade before anything changes: the diff against the running stack and a check for any inputs the newer version requires but the stack does not have yet.

## Apply and watch

* Applying the update produces a new release and moves the stack to the newer template version.
* Watch the recovery state through the upgrade rather than assuming it finished.
* A template upgrade can be rolled back if the new version misbehaves.

## Status meanings

* up\_to\_date: the stack matches the latest published template version.
* update\_available: a newer version exists and can be previewed.
* upgrade\_blocked: the upgrade cannot apply safely as-is — resolve the blocking reason first.
* unknown: provenance could not be resolved; investigate before forcing changes.

## Expected result

<Check>
  The stack moves to a new template version with upgrade history preserved.
</Check>

## Related guides

<CardGroup cols={2}>
  <Card title="Template upgrade safety and service notes" href="/templates/template-upgrade-safety">
    Understand why an upgrade is safe, risky, or blocked, and how template readiness notes should influence operator decisions.
  </Card>

  <Card title="Template inputs and secrets" href="/templates/template-inputs-and-secrets">
    Understand which template values are required, which are sensitive, and how they affect rendering and upgrades.
  </Card>

  <Card title="Stack troubleshooting" href="/stacks/stack-troubleshooting">
    Common stack-side failures around placement, logs, health, template drift, and restore behavior.
  </Card>
</CardGroup>