By name: erlang description: Erlang concurrent programming with OTP. Use for .erl files.
Erlang
Erlang powered WhatsApp and the telecom backbone. OTP 27 (2024) adds a JSON module and triple-quoted strings. It is the foundation of Elixir.
When to Use
- 99.9999999% Reliability: Hot code reloading, supervision trees.
- Massive Concurrency: Lightweight processes (millions per node).
- Distributed Systems: Distributed Erlang nodes connect natively.
Core Concepts
OTP
Open Telecom Platform. Behaviors like gen_server (Generic Server).
Let it Crash
Don't catch exceptions. Let the supervisor restart the process.
Message Passing
Pid ! Message. No shared memory.
Best Practices (2025)
Do:
- Use
rebar3: The standard build tool. - Use
maybe: The new monadic-like flow control (enabled by default in 27). - Use
json: The new stdlib JSON parser (faster/safer).
Don't:
- Don't optimize pre-maturely: Profile first. Messages are copied.