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README.md

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+# devplatform-template-go-service work as expected
+
+This project is a template project to bootstrap golang repositories using the Giant IDP.
+Please read the notes below to understand how this repository works and is kept up to date.
+
+## Updating the template
+
+If you want to update any files that are templated when a new project is created, you should
+create a new topic branch and then a new PR from that branch against the `main` branch.
+For each PR, a separate github action is run to create a preview PR with the changes applied (a sub-PR).
+That sub-PR runs the templating logic against your topic branch and then compares the rendered result with
+the current status of the `rendered-project` branch. For the sub-PR, all tests are invoked and their status is reported in the sub-PR. The original PR will have a link to the sub-PR, so you can check its status.
+Once you're happy with the change in the sub-PR, you should merge it (the changes will go to `rendered-project`
+branch). Once that's done, you can merge the original PR as well.
+
+### Renovate
+
+Renovate correctly detects dependencies and creates PR against the `main` branch.
+
+### Example
+
+1. A topic branch and a PR created by renovate to update a github action in the `project-template`` directory
+   <https://github.com/giantswarm/devplatform-template-go-service/pull/118/files>
+
+2. A comment in the PR to the templated sub-PR and its check result
+   https://github.com/giantswarm/devplatform-template-go-service/pull/118#issuecomment-2580213836
+
+```
+Comment on #118 chore(deps): update sigstore/cosign-installer action to v3.7.0
+Pull request #136 was created to preview the result of this PR.
+Make sure you review and accept the created PR before you merge this one here.
+<https://github.com/giantswarm/devplatform-template-go-service|giantswarm/devplatform-template-go-service>giantswarm/devplatform-template-go-service | Today at 2:45 PM | Added by GitHub
+```
+
+3. The templated sub-PR itself
+   https://github.com/giantswarm/devplatform-template-go-service/pull/136