Elixir is amazing! The original author, José Valim, took a brilliant approach: Take a 30 year-old battle-tested highly-parallel VM, and build a modern language on top of it. Syntax is inspired by the good parts of Ruby (very clean), but nothing comes close in terms of the ease of parallelism... it's so natural, and insanely fast.

The unit tests are what convinced me this will be the next big thing. Beautifully clear syntax, succinct tests, and most importantly: Parallel out of the box. Hundreds of unit tests run instantaneously. Ruby TDD setups run tests that changed with maybe 1-2s lag... Elixir runs all the tests so fast that, at the beginning, I wasn't sure the tests were running.