gulp tasks npm gulp build fails

[apamwach]

issue definition
As instructed after cloning the repo, and updating packages after running npm install everything works fine untill the next step where npm gulp build squarks

Expected behaviour
npm gulp build runs successfully.
Actual behaviour
Usage: npm

where is one of:
access, adduser, audit, bin, bugs, c, cache, ci, cit,
clean-install, clean-install-test, completion, config,
create, ddp, dedupe, deprecate, dist-tag, docs, doctor,
edit, explore, get, help, help-search, hook, i, init,
install, install-ci-test, install-test, it, link, list, ln,
login, logout, ls, org, outdated, owner, pack, ping, prefix,
profile, prune, publish, rb, rebuild, repo, restart, root,
run, run-script, s, se, search, set, shrinkwrap, star,
stars, start, stop, t, team, test, token, tst, un,
uninstall, unpublish, unstar, up, update, v, version, view,
whoami

npm -h quick help on
npm -l display full usage info
npm help search for help on
npm help npm involved overview

Specify configs in the ini-formatted file:
/home/$user/.npmrc
or on the command line via: npm --key value
Config info can be viewed via: npm help config

npm@6.9.0 /home/$user/.nvm/versions/node/v10.15.3/lib/node_modules/npm

Did you mean one of these?
up
help

steps to reproduce

1. Clone the repo
2. cd into the root directory
3. run npm install
   at first it will squark untill you update some puckages namely gulp-sass and related ones
4. run npm gulp build

[m-fin]

I'm getting this same error. Has anyone figured this out?