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Darren Labithiotis
Verified Expert in Engineering
Software Developer
Millstatt, Austria
Toptal member since April 3, 2020
Bio
As a full-stack software engineer with a history of design and years of professional expertise, Darren has helped deliver rich customer experiences to thousands of users. He's driven and motivated to continuously measure and iterate solutions to achieve business goals.
Portfolio
Kernel
TypeScript, React, NestJS, Prisma, Node.js, Google Cloud Platform (GCP), Figma...
Yara
React, React Native, GraphQL, TypeScript, Team Leadership, Agile...
Hablo
Cloudinary, CSS, JavaScript, CSS3, DevOps, Back-end, TypeScript, GraphQL...
Experience
- JavaScript - 11 years
- React - 9 years
- Node.js - 8 years
- TypeScript - 6 years
- MongoDB - 4 years
- GraphQL - 3 years
- PostgreSQL - 3 years
- React Native - 2 years
Preferred Environment
Google Cloud Platform (GCP), Datadog, MacOS, TypeScript, React, GraphQL, Jest, GitHub, NestJS, E2E Testing
The most amazing...
...tool I've built was a Slack bot to automatically detect and translate acronyms used in messages—to solve the age old problem of TLAs.
Work Experience
Senior Software Engineer
2021 - 2023
Kernel
- Acted as the principal developer for building a full-stack service to import data from external sources like Google Sheets, JSON, or CSV.
- Created management APIs of user data, implemented intuitive ACLs (Access Control Level) using Auth0 roles and policies, and sophisticated versioning and publishing utilizing dynamic foreign keys to retain strict DB constraints.
- Built a component library from scratch to match Figma designs for a Figma Plugin, allowing designs to select their data sources and apply content to Figma designs.
- Implemented image job system to batch process Cloudinary upload jobs using BullMQ.
- Helped build complex Auth0 PKCE system to work within the restraints of the Figma plugin ecosystem.
- Added e2e testing for the project, including mocking the complex Figma ecosystem.
- Built a microservices project that incorporated a CI/CD pipeline. This pipeline encompassed validation steps, including code linting, compilation, unit and integration testing, and deployment, all utilizing GitHub version tags.
Technologies: TypeScript, React, NestJS, Prisma, Node.js, Google Cloud Platform (GCP), Figma, OpenAI GPT-3 API, Remix, Auth0, Slate, Sentry, React Apollo, Cypress, BullMQ, Cloudinary, SEO Marketing, User Interface (UI), User Experience (UX), CSS, CSS3, Styled-components, Agile, CI/CD Pipelines, Microservices, REST APIs, GraphQL, HTML5, CSS4, Sass, Tailwind CSS, Architecture, Scrum
Senior React Native Engineer
2020 - 2021
Yara
- Implemented a new functionality for the existing mobile app that included refactoring older component-based components to functional hook-based components.
- Added end-to-end tooling for the React Native app, with a focus on performance and stability.
- Oversaw considerable refactoring to simplify a core aspect of the app to resolve a variety of bugs and issues.
- Incorporated the new tooling to improve the developer's experience and automation to avoid wasting time on repetitive work: For example, scripts to fetch dev tokens automatically.
Technologies: React, React Native, GraphQL, TypeScript, Team Leadership, Agile, Technical Leadership
Lead Software Engineer
2020 - 2020
Hablo
- Architected the whole front-end application utilizing the latest technologies: TypeScript, React, GraphQL, Cypress, Auth0, and more.
- Delivered pages and features requested by the client rapidly to achieve a working platform within three months, which included creating accounts, connections, posts, searches, and complex organizations with roles and permissions.
- Incorporated production-ready tooling to monitor the platform, from its health to what users were doing and errors in real time.
- Set up CI for a mono repository to deploy to pre-production environments, with flows to support deploying to production once tests (including end-to-end) passed.
- Built a staged image-loading system in React using Cloudinary. The component first loads and displays a very small blurry image while the full-resolution image downloads.
Technologies: Cloudinary, CSS, JavaScript, CSS3, DevOps, Back-end, TypeScript, GraphQL, Front-end, React, User Interface (UI), Architecture, Agile
Senior Software Engineer
2016 - 2020
Triptease
- Built a service that collects prices from online travel agents in real time and handles hundreds of requests in a minute; utilized caching and multiple strategies to avoid bot detection, like auto IP pooling and full browser emulation.
- Designed and built a performant service to manage clients' branding used by client dashboards and internal teams. It implemented an immutable database to have a built-in history of changes and deployed behind a CDN for performance.
- Developed pop-up widgets that had to run on external client sites and work in isolation (i.e., they could not mutate or affect host sites). These widgets delivered a rich experience to our client's guests and helped deliver uplift.
- Co-built Triptease's client platform that supported several teams and was used by clients to configure their suite of products and measure their performance with rich dashboards and analytics.
- Constructed a bespoke component library for Triptease's client platform, consisting of an extensible data list component, rich UX drop-drops, and reusable typography components.
- Created a spider scraping tool to scrape travel agent sites to obtain a list of hotel properties per country for Triptease sales leads. The tool also enriched this data with additional sources like Google, LinkedIn, and Tripadvisor.
- Encouraged teams to maintain and adopt new techniques and tools to ensure a healthy codebase.
- Built a scalable and highly available service to consume analytical events from all of Triptease's products, handling hundreds of requests a second. Utilized queues and serverless functions to handle requests with reliability.
Technologies: CSS, CSS3, WebStorm, JavaScript, Google Cloud Platform (GCP), SQL, MongoDB, TypeScript, React, Node.js, SEO Marketing, Google Chrome, Web Extensions, User Interface (UI), User Experience (UX), Python, Terraform, Koa, ParcelJS, Test-driven Development (TDD), Scrum, Agile
React Native Engineer
2016 - 2016
Star Citizen Mobile App
- Built a React Native mobile app for a highly anticipated game, Star Citizen. The app provided players with information about ships in the game. Although the game has a limited user base, it had over 3,000 active monthly users at its peak.
- Deployed the app to both iOS and Android without using any special code to cater to each.
- Built a custom scrapper to source all data for the app, as the game developer did not provide it officially.
Technologies: React, Amazon Web Services (AWS), JavaScript, Redux, React Native
Head of Development
2013 - 2016
Bopple Technologies
- Managed a team of people to deliver a mobile ordering platform. The team consisted of an iOS developer, an Android developer, two Java back-end developers, and one front-end developer.
- Built an HTML5 mobile app for the venue staff to process mobile orders via Boppl's mobile apps.
- Created an entire CMS back office for venues to manage their accounts and the products they sold.
Technologies: CSS3, Amazon Web Services (AWS), WebStorm, RequireJS, jQuery, Handlebars, Backbone.js, HTML, JavaScript, Less
Full-stack Developer
2015 - 2015
Prism Digital
- Built a job recruiters website and job board from the ground up. The website and the job board highlighted the company and allowed users to view, search, and apply for jobs (Prism-digital.co.uk).
- Implemented for the job board a rich API to allow 3rd-party job tools to post jobs in real time.
- Set up Google indexing to automatically expose jobs on Google's job platform.
Technologies: JavaScript, CSS3, Amazon Web Services (AWS), MongoDB, Passport.js, JADE, Express.js, Node.js, SEO Marketing
Experience
React Native App | Star Citizen Field Guide
A React Native mobile app that I built for a highly anticipated game, Star Citizen. The app provided players with information about ships in the game. At its peak, the app had over 3,000 active monthly users. It was built in the early days of React Native (around v2.0).
React Native App | Name Combos
Name Combos is a simple app that generates baby names and shows a preview to help parents decide what to name their baby. The app was built using Expo to utilize simple development and over-the-air updates.
Hablo
https://myhablo.comHablo connects you with your global travel network to connect with you, your business, and our industry. It's a social platform that allows users to connect and convert.
I was the lead engineer building the application from the ground up.
The front end used the latest technologies like React, Apollo (GraphQL), Webpack, and Auth0. The back end used NestJS and PostgreSQL hosted on GCP via Cloudflare. We also used Cypress for our E2E testing and Jest for unit testing. All code was written in TypeScript using tools like Prettier and ESLint to ensure styling and patterns.
I was the lead engineer building the application from the ground up.
The front end used the latest technologies like React, Apollo (GraphQL), Webpack, and Auth0. The back end used NestJS and PostgreSQL hosted on GCP via Cloudflare. We also used Cypress for our E2E testing and Jest for unit testing. All code was written in TypeScript using tools like Prettier and ESLint to ensure styling and patterns.
React Native App | Yara AtFarm
A React Native app to help farmers grow fields in the most efficient way possible. I oversaw the release of the app, completing several key features in order to release it properly. I worked on refactoring the app to support new GraphQL APIs, ensuring the app worked offline, updating RN versions, and implementing new UI/UX flows.
Online Travel Agent Price Check Widget
https://triptease.com/en/platform/A React widget to display prices from popular online travel agents in real time. The widget was designed to run in an iFrame on hotels' websites to ensure guests that the price the direct hotel website displayed was the cheapest. The widget ran on 10,000+ hotels and worked on all browsers. I was responsible for building the widget and the back end to scrape online travel agents' websites in real time.
Kernel Content Design Tool for Figma
A Figma tool to ingest real product data from JSON, CSV, Google Sheets, or APIs to use in their designs. The tool allows designers to create configurations to map their design layers to real data, including images. It speeds up designers' workflows by enabling them to search and configure realistic data in their designs effortlessly.
Education
2005 - 2008
Bachelor of Science Degree in Computer Games Design
University of Staffordshire - Staffordshire, United Kingdom
Certifications
FEBRUARY 2015 - PRESENT
MongoDB Certified
MongoDB University
Skills
Libraries/APIs
REST APIs, Node.js, React, React Navigation, Puppeteer, Antd, jQuery, Backbone.js, Passport.js, Handlebars, RequireJS
Tools
WebStorm, Webpack, Prisma, Terraform, Git, React Apollo, Docker Compose, BrowserStack, Sketch, Babel, Mocha, Photoshop CS6, Slack, Auth0, Expo, GitHub, Figma, Sentry
Languages
HTML5, CSS3, Sass, JavaScript 6, JavaScript, TypeScript, CSS, HTML, Less, GraphQL, JADE, Bash, SQL, Python, CSS4
Frameworks
Jest, Redux, Express.io, React Native, Express.js, Koa, Fastify, Cypress, Next.js, NestJS, Remix, Tailwind CSS
Paradigms
Agile, Scrum, DevOps, Microservices, Test-driven Development (TDD), E2E Testing, Microservices Architecture, Desktop Web Design
Storage
MongoDB, NoSQL, Google Cloud Datastore, Datadog, PostgreSQL
Platforms
WordPress, AWS Lambda, Kubernetes, Docker, Google Cloud Platform (GCP), Amazon Web Services (AWS), MacOS, Heroku, Firebase, Google Chrome
Other
Styled-components, APIs, Front-end, Storybook, User Interface (UI), CI/CD Pipelines, Architecture, Cloudflare, CSS3 Animation, GitHub Actions, Back-end, Apollo, Apollo Server, Full-stack, Cloudinary, ParcelJS, User Experience (UX), RESTful Microservices, Coding, Game Design, 3D, OpenAI GPT-3 API, Slate, BullMQ, SEO Marketing, Web Extensions, Team Leadership, Technical Leadership
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