BEAM There, Done That with Roberto Aloi & Michał Muskała on Erlang at WhatsApp - Part 1

Part one of two with the WhatsApp developer experience team. This episode covers scale and operations; part two covers tooling and types.

Main points for the Elixir community:

• Michał came to Erlang from Elixir and describes the tooling gap as the biggest initial friction. He’s spent years closing it - which is where part two lives.

• The hiring point is worth repeating: WhatsApp doesn’t hire for Erlang experience, it hires good engineers and teaches them. The 30th employee was the first with Erlang experience. The implication for anyone building an Elixir team is the same.

• The anti-pattern with the most sustained production pain at this scale: overly dynamic code. Atoms as function names, runtime module resolution, anything that makes static analysis hard. It works. It also makes debugging, tooling, and navigation progressively more painful as the codebase grows.