$ zeek --version
zeek version 4.0.0-rc1

An accidental typo revealed a core-dump. You can replicate with the code snippet here:

$ cat crash.zeek

type mac: stringA;

event zeek_init()
{
        print fmt ("hello");
}

Core was generated by 'zeek -i ixl3 ../host-profiling.zeek'.

Program terminated with signal SIGABRT, Aborted.
#0  0x0000000801b171ba in thr_kill (

This answer on Stack Overflow might be a good starting point.

Hi

I have just got unifi-poller up and running in a Docker container - all good.

But I followed the instructions, and specified port 8443 for the Unifi controller (https://10.0.15.101:8443). This failed. Changing it to 443 worked.

grpcio-tools should be a setup dependency, not a runtime dependency. In turn grpcio and protobuf should be runtime dependencies.