Centos7 SystemD - Systemctl startup issue - centos

Question

I have my bash script which I set my service to run ExecStart on - now my bash script with run directly via the user 'staytus' starts and stops things as expected but for some reason that I do not under stand yet when I run it via systemctl it throws errors!
Now since it works fine running as the same user I have the service set to use that kinda tells me the problem is with the startup file.
[Unit]
Description=Starts up procodile which runs staytus
[Service]
User=staytus
Type=simple
ExecStart=/usr/bin/startup/start.sh
Restart=on-abort
[Install]
WantedBy=multi-user.target
I've tried adding a working directory, changing the user etc all with no luck - any other suggestions of what to try?
Oct 12 15:36:52 system-name start.sh: /usr/local/bin/procodile: line 10: require: command not found
Oct 12 15:36:52 system-name start.sh: /usr/local/bin/procodile: line 12: version: command not found
Oct 12 15:36:52 system-name start.sh: /usr/local/bin/procodile: line 16: syntax error near unexpected token `('
Oct 12 15:36:52 system-name start.sh: /usr/local/bin/procodile: line 16: ` str = str.dup.force_encoding("BINARY") if str.respond_to? :force_encoding'
Oct 12 15:36:52 system-name systemd: status.service: main process exited, code=exited, status=2/INVALIDARGUMENT

Answer 1

On Systemd the environment variables for a process run by ExecStart is not the same as on the user terminal.
See https://www.freedesktop.org/software/systemd/man/systemd.exec.html#Environment%20variables%20in%20spawned%20processes
You'd have to check the environment variables where it runs ok (maybe using set command on the terminal) and add the needed ones on the systemd service definition using Environment="VAR1=VALUE1" "VAR2=VALUE2". See https://www.freedesktop.org/software/systemd/man/systemd.exec.html#Environment