Error building image

Hey guys. I keep getting stuck at 80% when I run [tutor images build openedx] what could be the cause?
Here is the output

80% [1] additional asset processingTraceback (most recent call last):                       
  File "/openedx/bin/openedx-assets", line 218, in <module>
  File "/openedx/bin/openedx-assets", line 89, in main
  File "/openedx/bin/openedx-assets", line 128, in run_webpack
  File "/opt/pyenv/versions/3.5.9/lib/python3.5/", line 271, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['webpack', '--progress', '']' returned non-zero exit status -9
The command '/bin/sh -c openedx-assets xmodule     && openedx-assets npm     && openedx-assets webpack --env=prod     && openedx-assets common' returned a non-zero code: 1
Error: Command failed with status 1: docker build -t /home/jimmykk/.local/share/tutor/env/build/openedx

Finally fixed this.

What you need to do is stop your tutor images before running the build command.

The problem is that running webpack takes too much RAM on your server. I have the same issue in my CI… Stopping your platform frees some memory, thus allowing you to rebuild your images.