Rebar3

Definition

Official page: https://www.rebar3.org/

Source code: https://github.com/erlang/rebar3

Rebar3 is mainly a dependency manager for Erlang and Elixir projects, but it also offers several other features, like bootstrapping projects (according to several templates, following the OTP principles), task executor, build tool, test runner and is extensible by using plugins.

Installing Rebar3

Rebar3 is written in Erlang, so you need Erlang to run it. It is available as a binary that you can download and run. Just fetch the nightly build and give it execution permissions:

$ wget https://s3.amazonaws.com/rebar3/rebar3 && chmod +x rebar3

Place this binary in a convenient place and add it to your path. For example, in a bin directory in your home:

$ mkdir ~/bin && mv rebar3 ~/bin
$ export PATH=~/bin:$PATH

This last line should be put in your .bashrc. As an alternative, one can also link the binary to /usr/local/bin directory, making it available as a normal command.

$ sudo ln -s /path/to/your/rebar3 /usr/local/bin

Installing from Source Code

As Rebar3 is free, open source and written in Erlang, it’s possible to simply clone and build it from the source code.

$ git clone https://github.com/erlang/rebar3.git
$ cd rebar3
$ ./bootstrap

This will create the rebar3 script, which you can put on your PATH or link to /usr/local/bin as explained in the section “Installing Rebar3” above.

Bootstrapping a new Erlang project

To bootstrap a new Erlang project, simply choose the template you want to use from the list. The available templates can be retrieved by the following command:

$ rebar3 new

app (built-in): Complete OTP Application structure
cmake (built-in): Standalone Makefile for building C/C++ in c_src
escript (built-in): Complete escriptized application structure
lib (built-in): Complete OTP Library application (no processes) structure
plugin (built-in): Rebar3 plugin project structure
release (built-in): OTP Release structure for executable programs

Once you have chosen the appropriate template, bootstrap it with the following command (rebar3 will create a new directory for your project):

$ rebar3 new lib libname

===> Writing libname/src/libname.erl
===> Writing libname/src/libname.app.src
===> Writing libname/rebar.config
===> Writing libname/.gitignore
===> Writing libname/LICENSE
===> Writing libname/README.md

OBS: Although you can run rebar3 new <template> . to create the new project in the current directory, this is not recommended, because the bootstrapped files will use . (dot) as application and module names and also in the rebar.config, which will cause you syntax problems.