Found here: https://learn.onpop.io/contracts/guides/deploy-your-contract-locally/deploy-locally-on-a-solochain

Note: The contracts node will be running in the background of your machine. If at anytime you need to kill the process you can do the following:
Find the process ID by running the following command: lsof -i :9944
Kill the process by running the kill command and passing in the ID of the process:
kill -9 3537

I think whenever we spin up the ink-node for the users, the terminal should change to an interactive mode. If the user than ends it with ctrl-c the ink-node is automatically killed as well.