Simple go program that will test if a port is open by sending a TCP SYN packet to it. Demonstrates how to use RAW IP sockets in Go 1.x+.
gorawtcpsyn ip port
gorawtcpsyn 192.168.0.2 5656
Must run as root. This program is purposefully stupid/easy/dumb/simple.
The authors of gopacket (which this example uses), also has a few other examples like an ARP scanner and a SYN scanner in his repository here.