multipass build dies - possibly OOM killed

Testing a build in multipass with:-

export SNAPCRAFT_BUILD_ENVIRONMENT=multipass
snapcraft cleanbuild

Killed
Failed to run 'override-build': Exit code was 137.
An error occurred when trying to execute "sh -c 'cd che; /snap/bin/snapcraft snap --output che_6.10.0_amd64.snap'" with 'multipass': returned exit code 2.

Here's the (simple) yaml to reproduce it if you're inclined.

----8<----
name: che
version: '6.10.0'
summary: Eclipse CHE
description: |
  Next-generation Eclipse IDE. Open source workspace server and cloud IDE.

grade: stable
confinement: strict

parts:
  che:
    plugin: maven
    source: https://github.com/eclipse/che.git
    override-build: |
      mvn -e -DskipTests=true -Dfindbugs.skip=true -Dgwt.compiler.localWorkers=2 -T 1C -Dmdep.analyze.skip=true -Dlicense.skip=true -Pnative clean install
    build-packages:
      - golang

----8<----

I didn't get any kind of sentry option nor indication why it failed. I have run it again, and it looks like we have 1GB RAM and 4GB disk set aside for the VM. Is that enough I wonder?

multipass info confarreated-deacon
Name: confarreated-deacon
State: RUNNING
IPv4: 10.161.160.203
Release: Ubuntu 16.04.5 LTS
Image hash: c0d099383cd0 (Ubuntu 16.04 LTS)
Load: 1.64 0.87 0.35
Disk usage: 1.2G out of 4.8G
Memory usage: 132.7M out of 992.1M
Mounts: /var/lib/snapd/snaps => /var/cache/snapcraft/snaps