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README.md

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 ## ARC CWL RO-Crate Profile
 
 [Latest version](profile/arc_cwl_ro_crate.md)
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+## Contributing to this repository
+
+The default branch `release` of this repo is kept in sync with the latest release tag and the zenodo record. 
+
+Therefore, all contributions to this repo must target the `dev` branch, which is representing the work in progress for the next versioned release.