An example libp2p project that uses a Kademlia DHT for peer discovery and performs rpc calls. You can read about this project at ldej.nl/post/building-an-echo-application-with-libp2p.
$ git clone git@github.com:ldej/echo.git
$ go run .
2021/01/20 12:56:42 Host ID: QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz
2021/01/20 12:56:42 Connect to me on:
2021/01/20 12:56:42 /ip4/192.168.1.8/tcp/45363/p2p/QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz
2021/01/20 12:56:42 /ip4/127.0.0.1/tcp/45363/p2p/QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz
$ # open a second terminal
$ go run . -peer /ip4/192.168.1.8/tcp/45363/p2p/QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz
2021/01/20 12:57:45 Host ID: QmSP59U51bSsERKobDE4CyrChJ4uSWv6RV1kiAs51DLLRF
2021/01/20 12:57:45 Connect to me on:
2021/01/20 12:57:45 /ip4/192.168.1.8/tcp/39957/p2p/QmSP59U51bSsERKobDE4CyrChJ4uSWv6RV1kiAs51DLLRF
2021/01/20 12:57:45 /ip4/127.0.0.1/tcp/39957/p2p/QmSP59U51bSsERKobDE4CyrChJ4uSWv6RV1kiAs51DLLRF
2021/01/20 12:57:45 Connection established with bootstrap node: "{QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz: [/ip4/192.168.1.8/tcp/45363]}"
$ # open a third terminal
$ go run . -peer /ip4/192.168.1.8/tcp/45363/p2p/QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz
2021/01/20 12:59:06 Host ID: QmPLsZDrgPLFie9PkvrdBbiMa8C5W9eKjZ429kimkP2SB8
2021/01/20 12:59:06 Connect to me on:
2021/01/20 12:59:06 /ip4/192.168.1.8/tcp/42967/p2p/QmPLsZDrgPLFie9PkvrdBbiMa8C5W9eKjZ429kimkP2SB8
2021/01/20 12:59:06 /ip4/127.0.0.1/tcp/42967/p2p/QmPLsZDrgPLFie9PkvrdBbiMa8C5W9eKjZ429kimkP2SB8
2021/01/20 12:57:45 Connection established with bootstrap node: "{QmNpf6rQUFFTR9syqLASvzTsfDdBaUYvu3QkgVMXodyJUz: [/ip4/192.168.1.8/tcp/45363]}"Each node sends a message to all peers every second, and each peer responds with an echo message.