$ is not a function

Hi, I am trying to implement a conference UI by myself using the lib-jitsi-meet library. Therefore I included a local copy of lib-jitsi-meet.min.js as a script tag. JitsiMeetJS.init() seem to work but new JitsiMeetJS.JitsiConnection() does not. It fails with “Uncaught TypeError: $ is not a function”. Is there any additional library I have to import? I didn’t read anything about it.