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README.md

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+# datalab-purl
+
+This repository contains a simple resolver for links to entries in different
+[*datalab*](https://github.com/datalab-org/datalab) instances that are part of the 
+[*datalab* federation](https://github.com/datalab-org/datalab-federation).
+
+The latest *datalab* federation list is pushed to ghcr.io and this repository
+builds the ghcr.io/datalab-org/datalab-purl image with nginx configs containing
+the appropriate redirects.
+This container runs at https://purl.datalab-org.io and resolves prefixed refcode links to the
+correct instance, e.g., https://purl.datalab-org.io/demo:1234 resolves to item
+`1234` on the *datalab* demo instance at https://demo-datalab-org.io/1234.