hello, i'm oli.

come and discover my work

Refresh Healthy Talos Inkode Hangman

Latest Blog Post

5th november 1955 i apologise, but an error occured; please refresh the page. thanks.

about me.

Hello, my name is Oli Callaghan, and I am an aspiring young developer, currently studying at Colchester Royal Grammar School. I am particularly interested in developing for the modern web, and have extensive experience in web design, writing JavaScript for the server and client and utilising Docker in development and production.

Latest Blog Post

13th january 2017 load balancing docker containers

Older Blog Posts

11th january 2017 running production databases inside docker

9th january 2017 making a site monitor with nodejs and docker

My Projects

Refresh Healthy Talos Inkode Hangman


Refresh was a project conceptualised and developed within a week at the YRS Festival of Code 2015. The principal role of the project was to provide an easy, simple and intuative platform for users to revise for any exam, provided with an exam syllabus. We identified that the main problem with modern online learning environments is that the data driving them is either high quality but very low in quantity, or low quality and high in quantity, and so we devised a plan to utilise the extraodinary amounts of data available online at sources indexed on popular search engines, using this content to formulate challenging exam questions that would test the user's ability and develop their understanding. We then use data collected from user interactions to focus questions and revision time on subject areas which the user finds more challenging. We hope that this proof-of-concept demonstrates the ability of the world wide web as a data resource and encourage you to check out the project here.



After being invited to the Open Data Institute’s Summit 2015, we took part in a hackathon whereby we were briefed to develop a food based application that utilised open data in some form. Having spent a very short period of brainstorming, we settled on the idea to write a program to calculate the amount of time it would take exercising to burn off the calories consumed in a meal. To accomplish this, we utilised a dataset that contained the calorific content of hundreds of thousands of different foods, and set up a search field to select the food eaten. Upon entering a little bit of basic information such as weight, gender and age, we carry out a set of complex calculations to deduce the amount of time required swimming, running and walking to burn off the meal. In total, the project was fully designed and developed in under 4 hours. The finished application can be found at the link below.



Talos is a joint concept developed by Oli Callaghan and Finnian Anderson, that monitors the uptime of sites, and is able to alert the monitor when the site goes down. It utilises Docker to create and destroy site health monitors, written in NodeJS, whilst also utilising Docker containers for the storage of user data, serving front-end files, and providing an interface for Alexa to read live updates on site health. The application can be experimented and used at the link below, and the full source code can be found on Github.

source code


Inkode is a new cloud platform that aims to simplify and streamline the development pipeline from development to deployment into one simple and uniform process at a reasonable price for small developers. Powered by Docker, the entire platform utilises Docker containers to isolate interface nodes serving as a control management system, whilst simlultaneously employing the power of HAProxy to load balance traffic between these containers. The main infrastructure driving Inkode is a collection of dedicated servers controlled by the Docker containers, running XenServer which is a hypervisor that allows for the virtualisation of servers amongst these large dedicated servers. In order to cope with traffic and increase efficiency of the system, the entire platform is written using NodeJS, an event driven, non-blocking server-side programming language that makes huge leaps in performance for IO tasks. Inkode aims to launch within the next few months, and will be live below.


Hangman Advertising and Agile Bank

During the summer of 2016, I amongst a group of others were invited to work at BT Martlesham Heath in the customer showcase to develop new products and innovations to display for prospective investors. As they were currently renovating the bank showcase, I was involved in the refurbishment and redesign of a cash point within the premises that utilised a palm print recognition system to validate the identity of the user. In addition to this, I was part of the small team that was involved in developing a ground breaking new technology that allows phones hung by their charging cables to act in an array as one in a large screen. After taking a picture of the set up of phones, we utilised image recognition to find the positions of the phones, identify their locations, and then stream cropped parts of a video to them over Wi-Fi. The entire project was vast and extensible, providing a robust framework for advertisements, and can be found at the BT Customer Showcase at Martlesham Heath.

hangman blog

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