All of our instances are reported as launched on ubuntu-core-18 now, due to strict confinement and base: core18. We should try and find a way to reach out to get the actual host OS.

https://github.com/canonical/multipass/blob/d9a72641a254a0613fe4344aa3cb93a67a6b055b/src/daemon/daemon.cpp#L116-L117

Using the following YAML should output warnings per offending spec instead of ignoring them silently.
Example:

footloose create
WARN[0000] Options under "spec.ignite" for "manager-%d" are ignored when using the "docker" backend
WARN[0000] Options under "spec.ignite" for "worker-%d" are ignored when using the "docker" backend
INFO[0000] Docker Image: quay.io/footloose/ubuntu18.04 prese

Some old programs versions can be found here if someone needs them to test old exploits for instance.

The check block in the peer-communication.ts example should be updated to the latest fork.

The following PR can be used for guidance ethereumjs/ethereumjs-devp2p#54 (this is missing the header RLP though).