Using p5js as a PWA as per these steps > https://medium.com/p/d5b9d0a1d726

How to set-up the hotspot to start at boot

1. Start the WiFi hotspot manually from the toolbar
2. Use "nmcli connection" to discover the UUID of this network
3. Use "nmcli connection show UUID" to show the properties of this network
4. Use "nmcli connection modify UUID connection.autoconnect yes connection.autoconnect-priority 100" to have it start automatically
5. Use "nmcli connection show UUID" to make sure these values were set

How to make the web-server a service

1. sudo ln -s /home/pi/hotdata/hotdata.service /etc/systemd/system/hotdata.service
2. sudo systemctl daemon-reload
3. sudo systemctl start hotdata
4. sudo systemctl enable hotdata
5. sudo journalctl -fu hotdata