Vasilis Kortsimelidis

I led a front-end team of two to deliver the customer care pages for the ASOS web team. I managed expectations between different players, such as the SEO, A11Y, and security teams. In addition to reducing the number of calls to customer service agents, this project also reduced ASOS's costs.

Pharos is a command-line tool I built in Rust that traces vulnerable JavaScript dependencies. It walks a project's dependency tree so you can see not only that a vulnerable package is present, but also which packages pulled it in, which makes triaging audit output on large front-end codebases far quicker. A personal project built to work more deeply with Rust while solving a practical problem I kept running into.

In this project, I developed the MVP and then helped create the final website.

With the website's help, the brand increased its awareness of Generation Z–the target audience–and boosted sales for the business.

It was my responsibility to develop the front end for the largest airline company in Greece.

The website was also compliant with WCAG 2.0 guidelines, which helped users, especially those who use keyboards, navigate.

Aegean Airlines won the Sitecore Award for "Best Site of the Year" and "Best Use of Content Management" for this project. More information about this award can be found at http://www.sitecore.com/company/news-events/press-releases/2016/11/aegean-airlines-wins-site-of-the-year/.

I developed every HTML template and animations for Novasports.gr, a premium sports service owned by Forthnet Group in Greece, using JavaScript. Originally known as Supersport, the company launched in 1994 as Greece's first premium sports service.

With this newly redesigned portal, the user experience has been improved.

This React Native app allows users to save their location and get directions later. The purpose of this project was to learn more about React Native.

It was previously published on Google Play, but the code is still available in the above-mentioned GitHub link.

This app, built in Angular 1, helps users find bus stops in London. The Google Maps API is used to render all the bus stops based on the location input.

The code is available at https://github.com/vaskort/geocoding-api-web-app

Using a location input, this React web app renders the weather temperatures for the next few days based on the provided location input.

The code is available at https://github.com/vaskort/weather-app.

I developed the pixel-perfect front end for many important website pages, including the navigation and order summary. For that, I effectively engaged with all team members, including developers and designers, and proactively raised issues when they arose. Also, I helped raise and fix front-end inconsistencies across the website, improving overall consistency and user experience and fixing bugs on the desktop, iOS, and Android versions.

I made the website accessible according to ADA and WCAG guidelines, which improved the user experience, especially for keyboard users, by enhancing and refactoring the JavaScript code whenever necessary while reviewing accessibility requirements.

During my review of web accessibility requirements, I refactored any CSS code to reduce its size, and the Shopify templates were updated or refactored so that I could develop accessibility requirements.

I improved all pages to 100% web accessibility based on the Google Chrome audit.

Based on the provided designs, I entirely developed the pixel-perfect front end of the React app. I refactored some React code wherever needed to improve readability and reusability.

As a result of my proactive approach to providing feedback about the designs, the UI across the web application became more consistent.

During a concentrated one-hour user research session for a leading AI company, I provided crucial insights into user interaction and behavior. I gave real-time feedback and intuitive suggestions on their AI application's UI, contributing to possible improvements in its design and usability. Throughout this process, I detected and reported several software bugs within the user testing phase, thereby aiding in immediate quality assurance measures. Additionally, I identified instances of user frustration and promptly suggested ways to enhance the overall user experience. This brief yet focused engagement allowed me to significantly contribute to the refinement of the app's functionality and user satisfaction.

A metronome app built using Electron. This robust and reliable app provides precise beat tracking essential for practice and performance. It ensures stability and accuracy; it was initially developed for use with Rust and the Neon CLI, but optimized with JavaScript for the best balance of performance and efficiency. This app is perfect for anyone seeking to perfect their timing and rhythm skills. It is available as a paid app on the Mac App Store, with the opportunity to try before you buy. It is a simple solution for your complex rhythm needs.

Symfreq is a command-line tool I built in Rust that identifies the most frequently used symbols in a source codebase. It scans source files and ranks identifiers by how often they appear, which makes it easy to see which functions, types, and variables carry the most weight in a project. I use it to quickly get oriented in unfamiliar repositories and to spot good candidates for refactoring or additional test coverage. This is a personal project built to explore Rust and static source analysis.

A technical article I wrote on building a reliable React testing setup with Vitest and React Testing Library. It covers configuring Vitest for a React project, choosing queries that reflect how users actually interact with a component, handling asynchronous behavior, and avoiding the brittle patterns that make a test suite expensive to maintain. It's published on Medium.

A technical article I wrote explaining how to unit test custom React hooks using React Testing Library and Jest. It walks through rendering a hook in isolation, asserting on state updates, handling asynchronous effects, and deciding what is worth testing in the hook itself versus in the component that consumes it. It's published on Medium.

A technical article I wrote for the ASOS Tech Blog on testing React and Redux applications. It covers where to draw the line between unit and integration tests, how to test reducers, actions and connected components, and how to structure a suite that gives real confidence without becoming a maintenance burden as the application grows.