Connect Four

Connect Four

  View on GitHub   View Demo


“Team” Approach

I recognize that having not worked professionally on a development team is a weakness on my resume. In order to simulate working on a team, I managed this projects via GitHub. I created milestones for each level (1-3 and Boss), issues for key features in each milestone, submitted pull requests for branches that fixed those issues, and then merged them from GitHub to close the issues.

Additionally, I attempted to maintain consistent convention across the board. Semicolons (JS), single quotes (JS), spacing, line breaks, directory structure, etc. were all maintained throughout.

I understand this is just a small portion of working on a team, but I wanted to make an effort to simulate doing so whenever able.


I opted to utilize Elixir’s umbrella project capabilities in order to manage the complexities of what essentially are three different applications: a command line interface, a web interface, and the game itself. Umbrella projects are an effective method for combining Elixir applications* that share common dependencies. While these applications are not completely decoupled, they are so loosely coupled that they can easily be split out into their standalone applications.

*Elixir inherited the term ‘application’ from erlang. I realize that these ‘applications’ function more like what is commonly referred to as a library.


The Game


The game itself runs on a GenServer that exposes an API interface that can be accessed by other Elixir apps on the cluster. Each game state is maintained within an Erlang Term Storage (ets) table, which allows for quick and easy access without the added overhead of a database layer. The board is stored as a map of MapSets, one player one, a second for player two, and a third for free spaces available.

For those not as familiar with Elixir, it’s worth noting that although lists look like arrays, i.e.: [1, 2, 3], they can only be accessed by transversing the list. MapSets are hash array map tries and allow access at O(log(n)) time vs the O(n) time it would take to traverse a list.

The AI is accessible to the game via module.



The Command Line Interface is a basic OTP application. Using an Elixir script from the command line, the CLI.Supervisor will launch the server. The server simply loops through various menu options, displaying content to the user and prompting for user input via IO methods. Connects with the GameServer, which manages the actual game.

The Web Interface

Docs (for the backend)

I used the Phoenix framework to create a JSON API backend, which in turn utilizes our GameServer API in order to manage and serve data. The docs listed above provide details on the API.

For the frontend, I used a simple ReactJS with a Redux store that interacts with the JSON API. Bootstrap 3 is used for CSS assistance.

Deployed Demo

  View Demo

I deployed this project to my Heroku account. It took a few iterations to get the configs right, as this was the first time I had deployed an umbrella app to Heroku.

Tech Stack

PHP for the plugin that interacts with the BandsInTown API.

Made for WordPress.

Author face

Dave Lively

Dave is a Support Engineer at SalesLoft, husband to Sarah, graduate of West Point, and avid Atlanta United supporter.

Recent post