Find out what's using those local TCP ports

kill-port

#!/bin/bash

# Kill process using the port
# Usage: kill-port <port-number>
# 
# Example:
#   $ kill-port 3000
#   Killed 🔪
if [ $# -eq 0 ]
  then
    echo "No arguments supplied: specify port"
    exit 1
fi

pid=`lsof -i :$1 -t`

if [ -z "$pid" ]
  then
    echo "No pid for port $1"
    exit 1
fi

kill -HUP $pid

echo "Killed 🔪"

which-port

#!/bin/bash

# Which process is using the port?
# Usage: which-port <port-number>
# 
# Example:
#   $ which-port 3000
#   -+- 87504 andrew node /Users/a/Projects/thing/node_modules/.bin/vite
# \--- 87573 andrew /Users/a/Projects/personal/thing/node_modules/esbuild-darwin-64/bin/esbuild --service=0.14.38 --ping

if [ $# -eq 0 ]
  then
    echo "No arguments supplied: specify port"
    exit 1
fi

pid=`lsof -i :$1 -t`

if [ -z "$pid" ]
  then
    echo "No pid for port $1"
    exit 1
fi

pstree $pid