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vm/tests/gh_workflows/NILayerTests/README.md

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+# Native Image Layer Tests
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+The Native Image Layer tests represent a way of automatically testing the Native Image Layer feature with the newest JDKs and the most popular Maven libraries, on a weekly schedule. The tests are run as a weekly GitHub action, defined in [ni-layers.yml](/.github/workflows/ni-layers.yml). 
+
+These tests work by running layer-building jobs for each library in [popular-maven-libraries.json](popular-maven-libraries.json), which is automatically generated and updated irregularly. The libraries that fail to build are added to [excluded-popular-maven-libraries.json](excluded-popular-maven-libraries.json) and are excluded from future buildings until their issues are fixed.