Mac – PostgreSQL, Docker, React

This company provides tools for financial advisors to help them analyze clients' property as assets and provide adequate financial products such as reverse mortgages.

• Introduced development processes such us evils ceremonies, retros, 3 amigos, ADRs;
• Focused team on small PRs and trunk-based development;
• Introduced micro-frontends and micro-backends instead of an old monolith application;
• Worked closely with owners and organizational clients to create a branded solution.

Classroom teachers and specialists can easily supplement and customize units by selecting lessons, anchor charts, graphic organizers, texts, and assessments from varied grade levels and use the “My Folders” feature to differentiate instruction for small-group remediation and acceleration for schools in the US. Our aim in this project was to rewire old applications to modern React with the new layout and new components with a refreshed backend.

• Was a Lead engineer for React redesign, upgraded React architecture from classes to functions, started using hooks and context instead of redux, and created standard components for better readability;
• Added multiple frontend-backed features like book sharing with notification, SSO with Google account, e-reader to non-printable books, integration with Google Classroom, improved content search and filtering, added different user types with other authorities;
• Maintained the app by continuing minor and significant bug fixes;
• Worked closely with the app's primary users, like school managers and head teachers, to improve their experience;
• Removed and refactored lots of code left by other developers.

A blockchain-based platform where developers can choose blockchain features to fit their games. It provides full integration of game and item purchases, NFT minting, and stakes to improve liquidity, community, and a marketplace for user-generated content.

It enables developers from anywhere in the world to collaborate on game creation in our unique cloud-based build environment. From the first login screen, the 3D world is both multiplayer and multi-developer. This is a unique feature that allows developers, designers and players to collaborate in fully immersive real-time, 3D environments.

• Led engineering efforts, a suite of services enabling users to upload, sell, and purchase assets for 3D MMO games
• Designed and developed the Auth Service, leveraging AWS Cognito for secure authentication and authorization.
• Co-authored system designs and architecture for the Alpha, Beta, and MVP versions of the entire platform's ecosystem.
• Established the foundation for a robust engineering culture by emphasising TDD, agile development, meaningful weekly goals, small PRs, and thorough code review.

One of the biggest car online retailers in the UK and EU where customers can buy cars online and get them delivered to their homes. This is an internal application for colleagues checking out cars for the customers. Users can find a particular car and check it out on their site. Then they follow the form with checks they have to perform on the car, such as visual, safety, battery, etc check. These checks are crucial for the business, and they strive to have the highest quality cars possible. Team leaders can see passed, failed, and resolved checks; and investigate historical checks and actions against cars. The whole app is serverless, using AWS Lambda functions and React frontend with data stored in DynamoDB.

• Engineering lead for the car CallOff service, a solution that streamlined and enhanced the quality inspection process before customer handovers;
• Designed and developed CallOff to efficiently handle daily inspections of hundreds of cars across the UK sites;
• Engineering lead for migrating inspections, call-offs, failures, and repairs data from AWS RDS to AWS DynamoDB, implementing new access patterns and data models;
• Assumed responsibility for merging the Failed Inspections Dashboard with the Vehicle Lifecycle system, resulting in a seamless and improved user experience while analyzing inspection failures on the sites;
• Continuously maintained and enhanced the Vehicle Lifecycle service, a solution to check the quality of vehicles when they are introduced to the system and track it along all stages for the EU and UK market;
• Successfully refactored Cypress tests, significantly reducing the pipeline runtime from 15 minutes to approximately 5 minutes;
• Refactored the Vehicle Lifecycle codebase by eliminating outdated components, introducing an improved folder structure, and updating documentation to facilitate smoother onboarding for new engineers;
• Acted as the primary engineer responsible for maintaining and updating translations (DE, ES, FR) for the Vehicle Lifecycle service;
• Maintained a strong focus on TDD, agile development, meaningful weekly goals, small PRs, and thorough code review through activities such as pair programming and one-on-one mentoring sessions with fellow engineers;
• Served as the initial point of contact for technical and non-technical stakeholders, explaining proposed solutions, providing estimates, and resolving issues.

Mac upgraded the main Vrbo page where users could pick up their holiday home. He worked on rewriting static pages into dynamically generated pages. This depended on the view the user was expected to see. They created several components to be reusable across the view. In this case, performance was very important as Vrbo has thousands of users per second. Mac worked on improving the page's web vitals and keeping them low.

The second project Mac was the lead engineer on was about introducing Datadog RUM to the company. They were using Sentry for page error triage. However, they used Datadog for general logging and they added Realtime User Monitoring as well.

• Led the development and implementation of Datadog Real User Monitoring (RUM) for the Vrbo brand, ensuring seamless user experience and performance optimization;
• Conducted comprehensive comparisons between Datadog RUM and Sentry, resulting in enhanced failure detection and quicker deployment times;
• Refactored static landing pages into dynamic generation, significantly improving performance and enhancing code readability;
• Optimized the loading and rendering time of property views by leveraging GraphQL for parallel requests;
• Collaborated on a machine learning module employing a multi-arm bandit approach, successfully boosting conversion rates;
• Utilized A/B tests and feature flags to enhance usability and increase conversion rates;
• Analyzed and enhanced page load times and performance metrics, including core web vitals such as LCP, FID, FCP, and CLS;
• Conducted technical interviews for junior and internship positions, evaluating candidates for technical proficiency and fit within the organization.

The main project was to build a business loan service. The company acquired another business doing that, but it was an old PHP app. They wanted to build a new, modern app with React, Nest, GraphQL, and MongoDB. The app allowed customers to go through the whole journey where they would answer questions about themselves and their business. Later they could connect to open banking to allow them to fetch basic financial information about their businesses. The app fetched, when allowed, their information from Companies House. With all that information, the app was able to match the customer with available loans.

In addition to that project, Mac worked on maintaining and updating the company's current apps for Energy and Broadband comparison for small and medium companies.

• Led the engineering efforts on a new loan finance app catered towards small and medium businesses;
• Undertook the redevelopment of an existing PHP app, rewriting it in JavaScript using Nest.js and TypeScript. Improved its Google Lighthouse score by 50 points and introduced accessibility features;
• Assumed responsibility for maintaining customer-facing microservices such as Energy and Broadband journeys while incorporating TypeScript to enhance the developer experience;
• Coordinated work, including design and architecture, between our remote office and headquarters;
• Acted as the engineering lead for a custom A/B tests and feature flags service, enabling the display of different products based on user needs and previous searches;
• Collaborated closely with product managers to devise new application solutions, refine architecture, and determine the optimal tech stack;
• Fostered a culture of Test-Driven Development (TDD) by implementing unit and end-to-end tests for both front-end and back-end components.
• Conducted real user tests with the new UI, working closely with user experience researchers to ensure a seamless user experience.

A web-based application for health professionals. The app originated at Oxford University. The user was able to go through the patient list and pick up the desired listing. Then, they were transferred to another view where they could see a CT scan of the patient's heart. That was the main part of the application. The user was able to see a 3D visualization of the heart and go through the layers. Additionally, the company developed an algorithm where they could predict cardiovascular disease risk by looking at the fat cells around the veins. The whole process was displayed in the browser as well. To obtain the 3D model of the heart, Mac created an ingestion service. This service would take medical grad CT image layers and process them into compatible images and then compose them into a 3D image.

• Founding engineer for the development of a cutting-edge medical web application designed to analyze the risk of cardiovascular diseases;
• Led the creation and ongoing maintenance of multiple microservices, meticulously built from the ground up using Docker;
• Constructed and maintained the Login App, Medical Data Display App, and Reporting App—essential front-end services utilized by medical professionals to access and interact with the product;
• Developed and continued to manage critical backend servers, including the Auth Server, Medical Image Processing Server, Reporting Server, and Medical Data Storage Server. These services, integrated with Postgres and Sequelize ORM, handle the processing, injection, and retrieval of medical images and data;
• Developed the Medical Image Processing Server, which is responsible for converting raw 2D CT scans of a patient's heart into highly detailed 3D models used for advanced visualization;
• Implemented comprehensive unit tests using Jest and Enzyme to ensure the quality and reliability of both front-end and back-end components.

E-learning hub with a social part to be used by companies for internal courses.

• Created and oversaw the development of RedPanda, an e-learning hub, utilizing Laravel as the back-end framework, Vue and Vuex for front-end functionality, and MySQL as the database;
• Played a key role as one of the primary engineers involved in building Curatr2, a gamified e-learning platform tailored for businesses;
• Developed Curatr2 using React and incorporating technologies such as Redux, Redux-Saga, TypeScript, and conducting thorough unit tests with Jest and Enzyme;
• Provided guidance and support to junior developers, assisting in their introduction to the product and ensuring a smooth onboarding process;
• Served as a mentor, sharing knowledge and fostering their growth within the team.

A project dealing with the replacement of old and heavy Excel files with a new web-based estimation app for internal use.

A Python web scraper to fetch the latest prices from the supplier websites to keep our DB up to date.

• Created innovative internal tools to streamline warehouse automation design, resulting in a notable 50% reduction in lead time for initial estimation.
• Fostered close collaboration with application and estimation teams to enhance product design and architecture, facilitating a short feedback loop for rapid and impactful improvements.
• Actively collaborated with the data science team to prototype cutting-edge auto-estimation tools, paving the way for more accurate and efficient estimation processes.
• Developed web scrapers to fetch real-time prices from supplier websites, ensuring the database remained up to date even in the absence of available APIs.