How to fix frequent nodemon error: address in use

August 8, 2019

nodemon throws 'address already in use' after few file changes/restarts.

Simple solution is to kill the port with kill -9 3000 (use the appr. port number)

But we wouldn't stop at that, would we?

create a nodemon.json file in the root with the below config.

    "events": {
        "restart": "kill -9 $(lsof -t -i:3000)",
        "crash": "kill -9 $(lsof -t -i:3000)"
    "delay": 100

change the port number accordingly

we are hooking kill -9 $(lsof -t -i:3000) command to restart/crash events of nodemon which finds the process id running on the given port number and kills it.