old/2.-Development-Guide/2.1.-Configure-Environment/2.1.5.-Erlang.md

+This section describes how to configure the Erlang environment to run experiments and
+develop code for the ETSI TeraFlowSDN controller.
+
+First we need to install Erlang. There is multiple way, for development we will be
+using [ASDF](https://asdf-vm.com/), a tool that allows the installation of multiple
+version of Erlang at the same time, and switch from one version to the other at will.
+
+- First, install any missing dependencies:
+```bash
+sudo apt install curl git autoconf libncurses-dev build-essential m4 libssl-dev 
+```
+
+- Download *ASDF* tool to the local account:
+```bash
+git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.10.2
+```
+
+- Make *ASDF* activate on login by adding these lines at the end of the `~/.bashrc` file:
+```bash
+. $HOME/.asdf/asdf.sh
+. $HOME/.asdf/completions/asdf.bash
+```
+
+- Logout and log back in to activate *ASDF*.
+
+*ASDF* supports multiple tools by installing there corresponding plugins.
+
+- Install *ASDF* plugin for Erlang:
+```bash
+asdf plugin add erlang https://github.com/asdf-vm/asdf-erlang.git
+```
+
+- Install a version of Erlang:
+```bash
+asdf install erlang 24.3.4.2
+```
+
+- Activate Erlang locally for TFS controller. This will create a local file
+called `.tool-versions` defining which version of the tools to use when
+running under the current directory:
+```bash
+cd tfs-ctrl/
+asdf local erlang 24.3.4.2
+```
+
+Erlang projects uses a build tool called
+[rebar3](https://github.com/erlang/rebar3).
+It is used to manager project dependenecies, compile a project and generate
+project releases.
+
+- Install rebar3 localy from source:
+```bash
+cd ~
+git clone https://github.com/erlang/rebar3.git
+cd rebar3
+asdf local erlang 24.3.4.2
+./bootstrap
+./rebar3 local install
+```
+
+- Update `~/.bashrc` to use rebar3 by adding this line at the end:
+```bash
+export PATH=$HOME/.cache/rebar3/bin:$PATH
+```
+
+- Logout and log back in.