Elixir

A dynamic, functional language designed for building scalable and maintainable applications. Running on the Erlang VM (BEAM).

When to Use

• High-concurrency applications
• Real-time systems (chat, gaming)
• Distributed systems that need fault tolerance
• Web development with Phoenix

Quick Start

IO.puts "Hello, World!"

list = [1, 2, 3]
doubled = Enum.map(list, fn x -> x * 2 end)

defmodule Math do
  def sum(a, b), do: a + b
end

Core Concepts

Processes

Elixir code runs inside lightweight processes (not OS threads) that are isolated and exchange information via messages.

pid = spawn(fn ->
  receive do
    {:hello, msg} -> IO.puts "Got hello: #{msg}"
  end
end)

send(pid, {:hello, "world"})

Pattern Matching

Used assignment and function dispatch.

{a, b, c} = {:hello, "world", 42}
# a is :hello, b is "world", c is 42

OTP (Open Telecom Platform)

A set of libraries and design principles for building fault-tolerant systems (Supervisors, GenServers).

Best Practices

Do:

• Use the pipe operator |>
• Leverage pattern matching
• Design with “Let it crash” philosophy (Supervisors restart processes)

Don’t:

• Use if/else excessively (use pattern matching or case)
• Mutate state (data is immutable)

References

• Elixir-Lang
• Phoenix Framework