To use this maven repo, you need to add this line into your project's pom
<repositories>
<repository>
<id>ngrinder-core</id>
<url>https://github.com/nhnopensource/nhnopensource.maven.repo/raw/master/{releases/snapshots}</url>
</repository>
</repositories>
Just append snapshots or releases to that root URL, as appropriate for your project’s dependencies.