This extension for Aether contains an installer that is safe for concurrent use.
'org.sonatype.aether:aether-concurrency:1.8'
<dependency>
<groupId>org.sonatype.aether</groupId>
<artifactId>aether-concurrency</artifactId>
<version>1.8</version>
</dependency>
<dependency org="org.sonatype.aether" name="aether-concurrency" rev="1.8"/>
"org.sonatype.aether", "aether-concurrency", "1.8"