Installing Elixir

Elixir doesn't run on its own — it compiles to BEAM bytecode, so installing Elixir also means having a compatible Erlang/OTP version installed alongside it. The good news is that modern installers handle this pairing for you.

Installing on your platform

macOS (Homebrew):

brew install elixir

Windows: download the installer from the official Elixir site, which bundles a compatible Erlang/OTP version, or install via choco install elixir.

Linux: most distributions package Elixir, but versions lag behind — using a version manager is usually more reliable.

Use a version manager

Because Elixir and Erlang/OTP versions are tightly coupled (a given Elixir release only supports certain OTP versions), the most robust setup uses asdf, a version manager that handles both:

asdf plugin add erlang
asdf plugin add elixir

asdf install erlang 26.2.1
asdf install elixir 1.16.0-otp-26

asdf global erlang 26.2.1
asdf global elixir 1.16.0-otp-26

This mirrors how most professional Elixir teams manage versions across a team and CI pipeline — pinning exact versions in a .tool-versions file so everyone (and every server) builds against the same runtime.

Verifying the install

Two commands confirm everything is wired up correctly:

elixir --version

Seeing both an Erlang/OTP line and an Elixir line is the sign that the pairing worked. If you only see an error about a missing Erlang installation, Elixir was installed without its runtime dependency — reinstall using a method (like asdf or the official installer) that bundles both.

Meet iex and mix

Two command-line tools ship with every Elixir install, and you'll use both constantly:

• iex — Interactive Elixir, a REPL for experimenting with code line by line.
• mix — the build tool: creates projects, manages dependencies, runs tests, and compiles code.

Try iex right now:

iex

iex> 1 + 1
2
iex> String.upcase("hello")
"HELLO"

Exit with Ctrl+C twice, or type System.halt().

A quick sanity-check project

mix new hello_elixir
cd hello_elixir
mix run -e "IO.puts(\"It works!\")"

mix new scaffolds a standard project structure (lib/, test/, mix.exs), and mix run -e executes a one-off expression against it. If you see It works! printed, your toolchain — Erlang, Elixir, and mix — is fully functional and you're ready to write real code.