Turns out all the work has been done by the OTP and kerl teams, all that is left is the OpenSSL install. I used the following runes:
git clone git://git.openssl.org/openssl.git
cd openssl
export MACOSX_DEPLOYMENT_TARGET=12
./Configure enable-rc5 zlib darwin64-arm64-cc no-asm
make
make test
sudo make install
Then installed Erlang & rebar3:
~/bin/kerl build 25.0-rc2 25.0-rc2
~/bin/kerl install 25.0-rc2 ~/kerl/25.0-rc2
. ~/kerl/25.0-rc2/activate
rebar3 local install
~/.cache/rebar3/bin/rebar3 shell
Success!
===> Verifying dependencies...
Erlang/OTP 25 [RELEASE CANDIDATE 2] [erts-13.0] [source] [64-bit] [smp:10:10] [ds:10:10:10] [async-threads:1] [jit]
Eshell V13.0 (abort with ^G)
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