prevent multiple concurrent "yarn installs": when the yarn cache is empty, deps must be fetched from network. multiple yarn instances performing fetches does not work reliably and leads to opaque errors
<goals>
<goal>yarn</goal>
</goals>
+ <configuration>
+ <!-- ensure only one concurrent 'yarn install' -->
+ <!-- when yarn cache is empty, multiple yarns performing network fetches frequently results in opaque errors -->
+ <arguments>--mutex network</arguments>
+ </configuration>
</execution>
<execution>
