They certainly seem to be going in the right direction:

Though I have my doubts they will be as lightweight as BEAM processes…

(Maybe we need a thread for ‘alternatives to the BEAM’? :D)

The reply?:

Memory

The Node or Python runtimes were meant to be run by individual people on their own servers. They were never intended to be run in a multi-tenant environment with thousands of other people’s code and strict memory requirements. A basic Node Lambda running no real code consumes 35 MB of memory. When you can share the runtime between all of the Isolates as we do, that drops to around 3 MB.

and for startup time of a process:

Because Workers don’t have to start a process, Isolates start in 5 milliseconds, a duration which is imperceptible. Isolates similarly scale and deploy just as quickly, entirely eliminating this issue with existing Serverless technologies.

So 3MB is clearly much more memory needed than the KBs from the BEAM, and 5ms seems an eternity in the BEAM land as pointed out in the Elixir forum by @malaire:

(Apologies, I’ll just copy-paste what I wrote in ElixirForum)

The only thing I am seeing in this idea is that somebody doesn’t seem to get the message that Javascript is not the future

“Stop trying to make JS happen. It’s not going to happen.” , as one meme goes.

The JS runtime is awful. As much as you try to fine-tune it it will inevitably spill its guts at the first sign of trouble. People spent weeks hand-crafting a Phoenix-like case for 1-2 million connections on a single server and it was a back-breaking work.

But that community doesn’t seem to be learning.