# Build Failure: SLF4J NoClassDefFoundError

### Problem <a href="#problem-when-running-maven-with-the-sealights-plugin-maven-fails-with-the-exception-error-injecting" id="problem-when-running-maven-with-the-sealights-plugin-maven-fails-with-the-exception-error-injecting"></a>

When running maven with the Sealights plugin, maven fails with the exception: `Error injecting constructor, java.lang.NoClassDefFoundError: org/slf4j/helpers/MarkerIgnoringBase`

Sealights relies on `slf4j-api` being provided by maven.\
For maven version 3.3.1 & 3.3.3 there was a regression issue where `slf4j-api` was not being provided by maven and failed a number of plugin. See [\[MNG-5787\] Moving from Maven 3.0.5 to 3.3.3 breaks plugins with some dependencies on the class path - ASF JIRA](https://issues.apache.org/jira/browse/MNG-5787)

### Solution <a href="#solution" id="solution"></a>

Updaing Maven to 3.3.9 and above should resolve this issue

### Related articles <a href="#related-articles" id="related-articles"></a>

* [Scanning Builds](/knowledgebase/setup-and-configuration/sealights-agents-and-plugins/java-build-tools-plugins/sealights-gradle-plugin/scanning-builds.md) (gradle plugin)
* [Incorrect SCM Links](/knowledgebase/setup-and-configuration/troubleshooting-faq/general/incorrect-scm-links.md)
* [Scanning Builds](/knowledgebase/setup-and-configuration/sealights-agents-and-plugins/java-build-tools-plugins/sealights-maven-plugin/scanning-builds.md) (maven plugin)
* [Capturing Unit Tests (UT) with the SeaLights Maven Plugin — Delta Guide](/knowledgebase/setup-and-configuration/sealights-agents-and-plugins/java-build-tools-plugins/sealights-maven-plugin/advanced-features/capturing-unit-tests-ut-with-the-sealights-maven-plugin-delta-guide.md) (maven plugin)


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