npm gets killed or errno 137

I know there are already lots of questions about this problem, but I simply can´t believe I´m running out of memory.

npm run dev

> mdbvue@4.8.1 dev /usr/www/users/****/****
> node build/dev-server.js

> Starting dev server...
ℹ ｢wdm｣: wait until bundle finished:
Killed
npm ERR! code ELIFECYCLE
npm ERR! errno 137
npm ERR! mdbvue@4.8.1 dev: `node build/dev-server.js`
npm ERR! Exit status 137
npm ERR!
npm ERR! Failed at the mdbvue@4.8.1 dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /usr/home/****/.npm/_logs/2018-11-11T02_31_12_055Z-debug.log

Running "free -g" return:

              total        used        free      shared  buff/cache   available
Mem:             31           1          18           0          10          28
Swap:             3           0           3

I can also post the debug log if that would help..