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+There are two important branches in this repository. 
+
+## The `release` branch
+
+This is the code were the Docker image published on Docker Hub is built from.
+It must only contain stable code and the most recent commit should be the commit increasing the version number in the `VERSION` file.
+
+## The `develop` branch
+
+It is where all the PRs land.
+When it is decided that enough features have landed, a [release is cut](Release).
+
+## Reason
+
+We once had the `master` branch.
+The `master` branch was the basis for the Docker builds.
+So when we merged features there, they were added to the Docker image immediately.
+
+To get around this we merged all relevant PRs manually and at once, then we cut a release and pushed all the features together to the `master` branch.
+That was not a nice workflow, also because that way PRs were kept open for a long time.
+
+So we introduced the `release` and `develop` branches as described above.
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