Something that I forgot to include in the keynote is that we are very adamant that Lumen not be viewed as competing compiler/runtime for the BEAM. We don't want that responsibility and we most certainly don't want any drama that could come about from the perception that we are trying to fork a community. We are 100% committed to the BEAM being the primary implementation for Erlang/Elixir and that we will follow as we target platforms that are currently unsupported by the BEAM. I can probably spell this out in the README at some point but I would considered Lumen broken if it ever decided to deviate from BEAM. Code that runs in Lumen should always run on the BEAM.