Installing Erlang

Installing Erlang means installing Erlang/OTP, a distribution that bundles the erl runtime shell, the erlc compiler, the BEAM virtual machine, and a large set of standard libraries collectively called OTP (Open Telecom Platform). Most developers today install OTP through a system package manager or a version manager rather than building it from source, since prebuilt binaries handle the native dependencies like OpenSSL and ncurses automatically.

On macOS, the fastest path is Homebrew with 'brew install erlang', which pulls a prebuilt OTP release and its dependencies. On Debian or Ubuntu Linux, 'apt install erlang' works for a quick start, though it can lag behind the latest OTP release; for production-grade control, many teams instead use kerl, a shell script that builds and manages specific OTP versions from source under your home directory.

On Windows, the Erlang Solutions installer or the official .exe installer from erlang.org provides a graphical setup that installs erl.exe, erlc.exe, and adds them to PATH automatically. Many Windows developers instead run Erlang inside Windows Subsystem for Linux (WSL2) with an Ubuntu distribution, since it gives the same apt-based workflow used on native Linux and avoids path or line-ending quirks that occasionally trip up native Windows installs.

After installation, open a terminal and run 'erl' to launch the interactive shell; a successful install prints the Erlang/OTP version banner and drops you at the '1>' prompt. Running 'erl -version' prints just the runtime system version without entering the shell, and 'erl -eval "erlang:display(erlang:system_info(otp_release)), halt()." -noshell' is a quick scripted way to confirm the exact OTP release number your PATH resolves to.

Because different projects can require different OTP releases, most working Erlang developers use a version manager: kerl for building and switching between arbitrary OTP source builds, or asdf with the erlang plugin, which reads a per-project '.tool-versions' file and switches OTP (and often Elixir) versions automatically when you cd into a project directory. This matters in practice because rebar3 build tool behavior, NIF compatibility, and some standard library modules change across OTP major releases.