The NVM Wrapper Plugin will fail builds if it fails to update NVM. This seems to occur intermittently when concurrent builds are running. Cases we have observed this are: 

• When creating a pull request we will often run the branch job and the merge job concurrently).
• When running parallel pipeline steps which both require NVM.

I suspect the root cause is that the plugin is trying to perform concurrent Git operations on the same repo, but there is insufficient information logged to confirm this.

From our perspective, possible solutions are:

• Use the existing NVM install if NVM fails to update
• Use a retry mechanism to try and avoid conflicts

Log excerpt:

=> nvm is already installed in /var/lib/jenkins/.nvm, trying to update using git
=> Failed to update nvm, run 'git fetch' in /var/lib/jenkins/.nvm yourself.