Hi, thanks for visiting!

My name's Sam Kelleher, and I am a Senior Full-Stack Web Developer / Software Architect based in London. This website mostly contains a sample of work from my portfolio, tips, and best practices for building web applications.

I am a Senior Full-Stack Web Developer and Software Architect based in London. This website consists of my portfolio, tips, and best practices for building web applications.
Crypto App using SwiftUI

Crypto App using SwiftUI

In my recent day-to-day work, I don't come into much contact with writing vanilla iOS apps directly. Despite being quite knowledgable in mobile app development, and the Swift programming language, I don't use these skills often. For this reason, I often in spare time (such as waiting at airports) write small apps, and review tutorials for using the latest advancements in programming languages like Swift, and the associated tooling like Xcode. Read more...

Ultra fast response times serving static files with WebAssembly Workers

Ultra fast response times serving static files with WebAssembly Workers

With trends moving to Serverless or Function-as-a-Service we've started building our web servers from instances of Express running inside Docker containers, to "functions" that instead run on managed infrastructure, responding to each request as they arrive. Many cloud providers supply this type of system which is fast, cheap, and very easy to maintain as all you have to do is upload your functions. Cloudflare in particular innovate further by replicating your worker to every edge node in their network, drastically limiting CPU + memory time, in exchange for response time as each worker 'instance' is located physically close to users. With previous approaches, worker instances were usually just located in a single region with redundant zones only; thus requiring a load balancer to be setup which is also not simple. Read more...

Statement on the UK exit from the EU 🇪🇺

I believe in inclusivity, openness, outwardness, a forward thinking future for all.

Brexit is the opposite of that.

The entire referendum was propagated by manipulating social networks for spreading targeted misinformation paid for by unknown foreign actors. What might not be obvious to those outside the UK, is that most mainstream media providers have all sewn an anti-immigration narrative for several years broadcasting radial right-wing opinions rather than fact based news. Factual misinformation has been promoted without question.

Democracy is an ongoing basis, to treat a non-binding referendum as binding and not give the public the change to reflect based on new information and instead use a flawed vote as a mandate to pursue the worst flavour of Brexit is just madness.

European citizenship is about being part of something greater than just the sum of my own nationality. While the EU is not by any means perfect, it stands as a triumph of human political achievement.

We are better off together than we are alone.

Fortunately I was able to personally retain my freedom of movement and European citizenship due to holding dual citizenship with the UK and Ireland.

MacroMealPrep App

MacroMealPrep App

I created this as a side project in my spare time as a way to plan ahead the food I would need to eat in a given week. The saying goes, "if you don't plan then you plan to fail". This goal of this app is different to other apps like MyFitnessPal which are geared around weight loss, and don't allow you to make plans in advance. Merely, they just track the food you eat, as and when you eat it. With my app, I wanted to put advance planning first, meaning, during the week, I would not need to spend mental energy thinking about what I should eat, when, or where. Read more...

React Isomorphic eCommerce Retail Experience

React Isomorphic eCommerce Retail Experience

A new Isomorphic React website that I describe as dumb, in that very little processing is done in storefront itself, instead, transactions are handed off to the API wherever possible. The goals that the website had to achieve was basically to not be Demandware. It should be uncoupled and agnostic from the datasource in all instances. It should be extremely fast, reliable, simple, and also customisable and theme-able. An anonymised responsive webpage is generated dynamically for each request, utilising significant in-app caching, and is frontend on the edge using Cloudflare which means the consumer gets a very fast and rapid render of the page, so even if the script takes a load to kick in on their browser, it happens before they begin to start interacting with the page. Read more...

Auto-Generated Release Notes in Docker for Webpack

Auto-Generated Release Notes in Docker for Webpack

This is an inline tool that, when used in a Continuous Deployment workflow can automatically generate full featured release notes when run as a Docker mounted command In particular, it is useful for Webpack build JavaScript projects that have outputted a stats file, as this tool is able to consume the data, and integrate relevant parts of it into the final release notes. The full release notes, and formatted bundle information relating to the Webpack build, are uploaded to GitHub and created as a release on the commit that generate it. It's able to compare the last prior release with the current one, and highlight important performance information, such as changes in the number of bundles, their chunk names, and their respective sizes; which are all relevant if you want to maintain an ongoing trend of light client releases. Read more...

React + Redux Administrative Panel SPA

React + Redux Administrative Panel SPA

A sleek and comprehensive single page application built using the latest React and Redux technologies. This application had to include comprehensive control capabilities including user management, data manipulation, search, a detailed analytics visualisation section, image editing with drag and drop.There was a lot to do, but with just a few tweaks the app is lightening fast to startup and initialize. One of my personal favourite things about Redux, and the flux pattern in general, is the predictability. As such, this project was one of with the fewest detected defects. Since what is on the screen is guaranteed to be generated by the data in state, any glitches or unexpected behaviour could be traced instantly using the Redux Time Machine. Read more...

Responsive Isomorphic Website with React, GraphQL, CSS Modules

Responsive Isomorphic Website with React, GraphQL, CSS Modules

Had the privilege of creating the public facing website for the company I work for, Blink. Since it's another greenfield site and React was strongly adopted by the company, it made a lot of sense to also construct the website using React.The content had to be editable by the marketing team, but since the parts of the website don't fit in a classic page type system that is popular on Wordpress, I integrated a third part content management platform, Contentful. Since the website would be Isomorphic, I had a Node Express server at my disposal, so I immediately got to work adding a GraphQL API that would be responsible for serving up the various strings and images stored in the CMS for the specific elements of these bespoke built pages. Read more...

P3 Image Color Experimentation

P3 Image Color Experimentation

2016 generation MacBooks and iPhones have a wide-gamut P3 display that show 25% 'more' red and greens compared to standard RGB monitors. So I began to experiment to work out what was needed to be able to use this extra color space when presenting images on web and native apps.Basically what I needed to work out was, when given an image that is using P3 color space, can I make a thumbnail from it without destroying the P3 colors and output a transformed image that is still in P3. Further that, to be able to display the specific P3 optimised images on devices that support it. Read more...

Pure Swift Instagram Queue App for iOS

Pure Swift Instagram Queue App for iOS

Sometimes it's nice to branch of into new technologies to keep perspective and knowledge of relevant stacks. This is my adventure into pure the pure iOS world with a simple Swift iPhone app. The app handles the basics, but should handle them well. Connecting to a HTTPS pinned API, download a data in JSON, cache it locally. Then parse it and use it to display data within the app.In this case, the app is a list of photos I have taken that I have uploaded to my website, but have yet to share on Instagram. I can track which photos are shared as I linked Instagrams post callback into my website, so new posts on Instagram can be matched to photos I've uploaded to my website by way of metadata matching. Read more...