Using Macros to Handle Environment Variables in Elixir

Here on my team at Manheim, we work in three or four, or maybe five, languages. We use Ruby and Elixir for building apis, Groovy for automating Jenkins, Bash for automating anything that isn’t automated in Ruby, Elixir, or Groovy, and…

Mock Modules and Where to Find Them

TL/DR

The compile path for a mix project defaults to /lib, but you can add environment specific load paths by defining a function in your mix.exs file that takes the Mix.env as an input. Reference this function by adding a elixirc_paths…

Elixir for the Little Things

A lot of blog posts, videos, books, and tutorials about programming Elixir tend to focus on the big things: web apps, web apps with Plug, web apps with Phoenix, web apps that need to handle 80 million concurrent requests, web apps that need to be web scale, big things. Big…

Preparing to Refactor with Property Tests

TL/DR

If you can think in properties, with or without a property testing library, your tests will support refactoring rather than being a barrier to it.

A Function of Parts

I recently lost my full time job. I’m working as a contractor, but one of the things about my life is that I’m legally obligated to have health insurance at all times, so I’m looking for a new full time job, which means I’m also looking at old code that I have hanging around on Github to see…

A Tale of Graphs and Darkness

TL/DR

1. Review of the previous two posts.
2. Small world networks have short distances between similarly connected nodes.
3. You can extract a small world of data from a small world network with a…

Deploying a Plug.Router Application to Heroku

For this blog post, we’re going to start with a fresh application, keeping our focus on maintaining a deployment to Heroku. The minimum project is a simple Plug.Router app that serves a web page of some kind. So it has to run from the command line…

Just the ‘T’ from ‘ETL’

Introduction

This is part 1 of a 2 part series in an N part series about about microservices. Our overall goal is to create three microservices with related data, host them on Heroku, and then look at strategies for coordinating those services.