After IPAM has a subnet whose CIDR contains -giaddr, and a pool:
make build
./bin/lattice-dhcptest -server 127.0.0.1:6767 -server2 127.0.0.1:6768 -giaddr 10.20.20.1 -n 40
That fake relay address must exist in a subnet you created in the plan. Watch Leases and lattice_dhcp_allocations_total.
Rebuild compose (make up) after code changes so dhcpd actually speaks DHCP.