Phoenix (Elixir)

Description #

Phoenix is a web development framework written in Elixir, known for building scalable, fault-tolerant applications with real-time capabilities and high performance.

History #

Phoenix was created by Chris McCord in 2014 and is built on top of Elixir and the Erlang VM. It brought modern MVC architecture to the Elixir ecosystem while embracing Elixir’s lightweight processes and concurrency model for blazing-fast performance.

Hello World Code #

defmodule HelloWeb.HelloController do
  use HelloWeb, :controller

  def index(conn, _params) do
    text(conn, "Hello, World!")
  end
end

How to Run #

Option 1: Online
https://play.elixirschool.com/

Option 2: Local

mix phx.new hello
cd hello
mix phx.server

Key Concepts #

• Built with Elixir/Erlang
• Real-time via WebSockets and Phoenix Channels
• LiveView for reactive UIs without JavaScript
• MVC architecture
• Functional programming style
• High fault tolerance
• Hot code reloading
• Optimized for concurrency
• Scalable microservices support
• Plug-based request pipeline

Try It Online #

https://play.elixirschool.com

Fun Facts #

• Phoenix can serve millions of connections using minimal memory, thanks to the Erlang VM.
• Its real-time system (Channels) handles live chat, notifications, and dashboards with ease.
• Phoenix LiveView allows full interactive UIs without writing a single line of JS.
• It’s used by fintech and healthcare startups for its reliability under load.
• Elixir’s actor model and Phoenix’s design make it ideal for building scalable APIs.

Resources #

Official site
Docs
GitHub
Community