How to Deploy Elixir Releases with Ansible

By on in Development, Elixir, Ops

In my last post, I described how to generate a platform-specific Elixir release. Now, the only thing left to do is to put it on the world wide web.

To follow along with this post, you’ll need a few things:

  1. An IP address for a remote machine (preferably running Linux) you want to deploy your application to.
  2. An RSA keypair, with the public key placed on that remote machine. Read more about how to do this here.
  3. Ansible (on your local machine). Read more about Ansible here.

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Idea: GenServers with Map-based state

By on in Development, Elixir

I recently gave a talk at Empex LA in which I talked about my desire to see simplifications and enhancements to using some of the OTP behaviors offered in Elixir. In this post I’m going to explore a simple improvement to the GenServer API that would make it a little easier to work with.

GenServers are processes that have state that can be transformed when the GenServer receives a message. This state is represented in a single value that is passed into the handle_call or handle_cast function.

This is easy to manage if your GenServer only needs to manage a single piece of information. But as soon as you find that your GenServer needs multiple pieces of information in state, you need to substantially refactor it.

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A Proposal: Elixir-Style Modules in JavaScript

By on in Development, Elixir, JavaScript

Moving your code towards a more functional style can have a lot of benefits – it can be easier to reason about, easier to test, more declarative, and more. One thing that sometimes comes out worse in the move to FP, though, is organization. By comparison, Object Oriented Programming classes are a pretty useful unit of organization – methods have to be in the same class as the data they work on, so your code is pushed towards being organized in pretty logical ways.

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Lightweight dependency injection in Elixir (without the tears)

By on in Development, Elixir

In our last Elixir blog post, “Functional Mocks with Mox in Elixir”, we discussed how testing across module boundaries could be made easier by creating a Behaviour for a collaborating module, then utilizing the wonderful framework Mox to substitute a lightweight mock module in tests.

This approach is well and good when you have very concrete module boundaries that are well-defined and coarse enough to warrant the ceremony of wiring up a behavior for a module boundary. But what if we aren’t necessarily interested in all the work in creating a mock, and we need something simpler and more lightweight?

Join us as we discuss some alternative ways to write lightweight tests across function or module boundaries.

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Comparing Dynamic Supervision Strategies in Elixir 1.5 and 1.6

By on in Development, Elixir

Classroom

Let’s say you’re managing complex process state in your Elixir application and you need a way to spin up and down new processes as your app runs. This requirement is known as dynamic supervision, the ability for a supervisor to add processes to its supervision tree at runtime.

This post will explain how to implement a process under dynamic supervision with Elixir 1.5, and discuss how Elixir 1.6’s new DynamicSupervisor is easier to configure and is more flexible.

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Razor: Hit the Ground Running With Your Next Phoenix Project

By on in Development, Elixir, Open Source

As the popularity of Elixir and Phoenix continues to grow, we find ourselves spinning up more and more Phoenix apps for our clients and side projects. At Carbon Five, we have a pretty good consensus on our favorite practices and tools. With each new app, we find ourselves repeating the same steps to bring in many of the same resources and processes.

We created Razor, an opinionated app generator, to save ourselves this time and trouble. Razor isn’t the only one out there, but it captures our common needs and preferences at Carbon Five pretty comprehensively. It also provides a great platform for discussion; we hope to watch Razor evolve as the Elixir ecosystem grows and we continue to learn.

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Elixir in the Trenches

By on in Development, Elixir

At Carbon Five, we’ve been getting excited about Elixir and Phoenix – with its promise of the productivity of Ruby and Rails without the performance penalty. We’ve used it for a few of our internal projects with great success, but we’re always wary of any new technology’s hype cycle. We wanted a bit more experience working with Elixir on a real project.

We recently had the opportunity to do so. The project was an iOS application that made heavy use of the device’s location services; users can share where they are and what they’re doing. We needed a backend for an API, and to keep all connected clients up-to-date. From the start, Phoenix and its channels seemed like a great fit. Today, we’d like to share some of what we learned.

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