For me the biggest thing is socket-based gen_tcp implementation as this makes step towards socket activation in Erlang. This will make possible to listen on restricted sockets without giving more permissions to the VM and will allow for lazy starting Erlang applications using launchd and systemd.

Sometimes you want to implement something that has an assigned port, like an SSH server, an HTTP server, FTP, you name it.

If we can do this without having to run the VM as superuser, or without having to rely on a third party program that acts as a “proxy”, we are a huge step forward.

Its not that there are not enough unrestricted ports, its just that the restricted ports have a purpose which we want to fullfil.

This is important too:

CPU quotas are now taken into account when deciding the default number of online schedulers.

This should mean that people using the BEAM in containerised environments (like Kubernetes) get much better performance (with less throttling) out of the box, without having to learn about/tweak the various flags.

Try the following:

# sudo apt -y install libwxgtk3.0-dev

# Ubuntu 20.04 LTS does not have this package for Erlang
# Need to install from source:
# https://www.wxwidgets.org/downloads/
# https://wiki.codelite.org/pmwiki.php/Main/WxWidgets31Binaries#toc2

sudo apt-add-repository 'deb https://repos.codelite.org/wx3.1.3/ubuntu/ eoan universe'
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 6856E1DB1AC82609
sudo apt update -y
sudo apt -y install libwxbase3.1-0-unofficial3 \
                 libwxbase3.1unofficial3-dev \
                 libwxgtk3.1-0-unofficial3 \
                 libwxgtk3.1unofficial3-dev \
                 wx3.1-headers \
                 wx-common

Yes but that method is practiced already with the inet driver since it is possible to open sockets/Fds which are already bound. You can open and bind a file descriptor with one program and then passing it to the Erlang VM on the command line. See the OTP source tree $OTP_ROOT/etc/unix/setuid_socket_wrap.c