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Luuk van Egeraat
Verified Expert in Engineering
JavaScript Developer
Brussels, Belgium
Toptal member since February 17, 2013
Bio
Luuk, a freelance TypeScript engineer with 15 years of experience, specializes in architecting and constructing robust, scalable applications using React and Node.js. His projects range from critical back-office systems for large enterprises to lean MVPs for startups. Beyond the technical implementation, Luuk focuses on bridging the gap between development teams and business goals. He understands that success depends not just on quality code, but on a team that works well together.
Portfolio
NEAS Inc.
Chatbots, ChatGPT, WhatsApp, OpenAI, WhatsApp Business, WhatsApp API, TypeScript
Kepler Cheuvreux SA
React, WebSockets, Cypress, Component Libraries, AG Grid, Electron, Tailwind CSS
neoBIM GmbH
TypeScript, Graphics, Next.js, JavaScript, React, Material UI
Experience
- JavaScript - 17 years
- Node.js - 14 years
- React - 10 years
- TypeScript - 10 years
- Google Cloud Platform (GCP) - 8 years
- Tailwind CSS - 5 years
- Next.js - 5 years
- Blockchain - 3 years
Preferred Environment
TypeScript, Next.js, React, Node.js, JavaScript, JavaScript 6, Google Cloud Platform (GCP), Tailwind CSS, Docker, Google Cloud
The most amazing...
...apps I've built as a TypeScript developer at Bayes Esports provide access management, real-time analysis, and AI/ML insights for Riot Games and ESL.
Work Experience
Lead Full-stack Software Engineer
2025 - PRESENT
NEAS Inc.
- Implemented GPT-5 on Azure with escalation to NEAS staff through a Function App.
- Integrated the Meta Cloud API with 360Dialog to support WhatsApp user queries.
- Built a custom WordPress plugin so users can access a chat widget to directly query the LLM.
Technologies: Chatbots, ChatGPT, WhatsApp, OpenAI, WhatsApp Business, WhatsApp API, TypeScript
Lead Full-stack Software Engineer
2024 - 2025
Kepler Cheuvreux SA
- Designed and implemented the architecture used by all their UIs.
- Added support for auto-updating, Electron-based React applications running on Windows.
- Built and maintained a component library published on their private npm registry that's used within all other UI repositories.
- Implemented real-time WebSocket connections for high-volume trading interfaces.
Technologies: React, WebSockets, Cypress, Component Libraries, AG Grid, Electron, Tailwind CSS
Senior TypeScript Engineer
2024 - 2024
neoBIM GmbH
- Redefined the MVP by providing a feasibility analysis.
- Refactored the authentication layer and global state management to support all desired SaaS functionality.
- Wrote a proposal to enhance communication and split responsibilities among the developers.
Technologies: TypeScript, Graphics, Next.js, JavaScript, React, Material UI
Senior TypeScript Engineer
2023 - 2024
TMD Technology Limited
- Wrote complex visualizations and graphs using Chart.js and ApexChart based on the exact requirements delivered by external customers or their in-house design team.
- Built custom React components used as a starter kit for onboarding customers, enabling them to sell their SDK to a broad range of customers.
- Provided feedback to SDK developers, enabling them to improve their software in preparation for the first customer.
Technologies: TypeScript, React, JavaScript, SQL, Chart.js, ApexCharts.js, Tailwind CSS, Responsive Web Apps
Principal TypeScript Engineer
2023 - 2024
Trigram Enterprises PTY LTD
- Built an AI-powered chatbot based on Llama 2 with TGI and protected it from DDoS attacks through the Pub/Sub model.
- Supported custom start and stop logic to the GCP GPU instances to lower operating costs.
- Implemented a custom interface in React with an admin panel and authentication system based on either manual or SSO (Google and LinkedIn).
Technologies: Python, Cloud, Full-stack, Full-stack Development, Chatbots, LangChain, Artificial Intelligence (AI), Google Cloud, Server Security, TypeScript, React, Tailwind CSS, Responsive Web Apps, Pinecone, OpenAI, ChatGPT, Firebase, Puppeteer, AI Tools
Lead Full-stack Software Engineer
2023 - 2024
Shica
- Integrated Stripe Connect, allowing users to be both customers or publishers earning money through the platform.
- Built an AI-powered plagiarism and quality checker for published documents using an LLM and various file conversion methods.
- Implemented a complex and custom interface built in React with a Next.js server, real-time WebSocket updates, and a Firebase database. It's scalable, containerized, secure, and built to be easily adaptable to new business requirements.
- Built an account system with various roles based on email or SSO (Google and LinkedIn).
Technologies: Web Development, Publishing, Financial Services, Finance, eCommerce, Startups, Early-stage Startups, High-tech Startups, Artificial Intelligence (AI), Large Language Models (LLMs), Lean Startups, Software as a Service (SaaS), TypeScript, React, Node.js, CTO, Google Cloud Platform (GCP), Firebase, Server Security, Front-end Development, Architecture, Next.js, Tailwind CSS, Responsive Web Apps, Stripe, Stripe Checkout, Payment APIs, Puppeteer, Firebase Realtime Database, AI Tools
Principal TypeScript Engineer
2022 - 2023
Open Cluster
- Contributed to Open Cluster, a cross-platform set of tools and solutions for scholarly funding, publishing, and conferences designed to build an equitable research, innovation, and communication ecosystem.
- Led the development of a payment processing system accepting crypto and credit card payment methods.
- Enabled the creation and trading of custom non-fungible tokens for academic research groups.
- Led the development of a system to process manuscript submissions for peer review and publication.
Technologies: TypeScript, JavaScript, React, Google Cloud Platform (GCP), Blockchain, Figma, HTML5, CSS3, JavaScript 6, Next.js, CSS, HTTP, HTML, Web Standards, Git, Linux, Sass, NoSQL, Lean Development, WebSockets, Google API, Mobile Web, Functional Programming, Object-oriented Programming (OOP), Bootstrap, Node.js, Extreme Programming, SCSS, GitHub, Tailwind CSS, Front-end, APIs, Responsive Design, Single-page Applications (SPAs), Redux, Webpack, Full-stack, SaaS, Docker, Firebase, Back-end, REST APIs, Cross-browser Compatibility, REST, Unit Testing, CTO, User Interface (UI), Charts, ChatGPT, Full-stack Development, Artificial Intelligence (AI), Google Cloud, LangChain, Architecture, JSON, Ethereum, Web3.js, Cryptocurrency, GraphQL, User Experience (UX), OpenAI GPT-4 API, Machine Learning, Cloud, Server Security, Front-end Development, ECMAScript (ES6), Responsive Web Apps, Stripe, Stripe Checkout, Payment APIs, Material UI, Puppeteer, Firebase Realtime Database, Blockchain & Cryptocurrency
Senior TypeScript Engineer
2020 - 2022
Bayes Esports
- Led the development of applications that manage and visualize esports-related data, specific to League of Legends (Riot Games) and Counter-Strike (ESL).
- Built an experimental low-latency video streaming service.
- Implemented three major applications for various in-house teams and Riot Games to manage and automatically process large amounts of esports tournament metadata.
Technologies: TypeScript, JavaScript, React, Figma, Node.js, JavaScript 6, WebSockets, SQL, NoSQL, HTML, HTML5, CSS, CSS3, Git, Mobile Web, Functional Programming, Object-oriented Programming (OOP), Tailwind CSS, Agile Software Development, Extreme Programming, Linux, Ajax, Lean Development, HTTP, Version Control, Bootstrap, Front-end, APIs, Amazon Web Services (AWS), Responsive Design, Single-page Applications (SPAs), Redux, Webpack, SaaS, Docker, REST APIs, Cross-browser Compatibility, REST, Unit Testing, D3.js, Data Visualization, User Interface (UI), Charts, Full-stack Development, Artificial Intelligence (AI), Architecture, JSON, User Experience (UX), Machine Learning, Python, Cloud, Server Security, Front-end Development, ECMAScript (ES6), React Redux, Responsive Web Apps, Material UI, Puppeteer, Sentry, AI Tools
Senior TypeScript Engineer
2018 - 2019
De Nationale Hypotheekbond
- Set up a new React-based application stack and implemented it in six calculation tools used by customers and professionals.
- Implemented an advanced testing suite using E2E testing using headless browsers and unit testing of all front-end software components.
- Set up CI deployment software connected to their Git monorepo.
Technologies: JavaScript, React, Node.js, JavaScript 6, Agile Software Development, Extreme Programming, HTML5, Web Standards, Functional Programming, Object-oriented Programming (OOP), SCSS, Version Control, Mobile Web, Bootstrap, Figma, CSS3, HTML, HTTP, Git, Linux, Sass, Ajax, Lean Development, Front-end, APIs, Amazon Web Services (AWS), Responsive Design, Single-page Applications (SPAs), CSS, Redux, Webpack, SaaS, REST APIs, Cross-browser Compatibility, REST, Unit Testing, Data Visualization, User Interface (UI), Charts, Architecture, JSON, User Experience (UX), Cloud, Front-end Development, ECMAScript (ES6), React Redux, Responsive Web Apps, Material UI
Senior TypeScript Engineer
2017 - 2019
SkillsTown
- Created software and provided support for all SkillsTown IT services.
- Was the lead developer in four major projects: Video Feedback Pro, Essential Editor, Skin Editor, and Request for Change.
- Integrated the Jira API to enable employees to directly request new features and bug fixes in the Request for Change application.
Technologies: JavaScript, PHP, SQL, NoSQL, SCSS, Svelte, Node.js, Agile Software Development, Extreme Programming, HTML5, JavaScript 6, Web Standards, Functional Programming, Object-oriented Programming (OOP), Version Control, Mobile Web, Bootstrap, Google API, CSS3, HTML, HTTP, Git, Linux, Sass, Ajax, Lean Development, Front-end, APIs, Responsive Design, Single-page Applications (SPAs), CSS, Webpack, Full-stack, SaaS, Back-end, REST APIs, Cross-browser Compatibility, REST, User Interface (UI), Full-stack Development, Architecture, JSON, User Experience (UX), Cloud, Chatbots, Server Security, Front-end Development, ECMAScript (ES6), React Redux, Responsive Web Apps, Material UI, Learning Management Systems (LMS)
JavaScript Developer
2015 - 2017
Software Skills
- Worked for a recruiting and testing company, maintaining and improving multiple modern web applications that provide services to customers and test candidates.
- Did full-stack development on all applications the company owns and runs.
- Designed and implemented a system that integrated various APIs, including our own developed Python API for testing the programming abilities of applicants.
Technologies: JavaScript, MongoDB, MySQL, AngularJS, Node.js, CSS, Agile Software Development, Extreme Programming, HTML5, JavaScript 6, Web Standards, Amazon EC2, Functional Programming, Object-oriented Programming (OOP), SCSS, Version Control, Mobile Web, Bootstrap, NoSQL, React, CSS3, HTML, HTTP, Git, Amazon S3 (AWS S3), Sass, Ajax, Lean Development, GitHub, Express.js, Responsive Design, Front-end, APIs, Amazon Web Services (AWS), Single-page Applications (SPAs), Redux, Webpack, Full-stack, SaaS, Back-end, REST APIs, Cross-browser Compatibility, REST, D3.js, Data Visualization, User Interface (UI), Charts, Angular, Full-stack Development, Architecture, JSON, User Experience (UX), Cloud, Chatbots, Server Security, Front-end Development, React Redux, Responsive Web Apps
JavaScript Developer
2013 - 2014
Remente
- Set up the build process and development environment using Brunch, Bower, PhoneGap, and the Amazon S3 API. Remente developed a mobile application for Karolinska Institute. The internet therapy department used this application to help ADHD patients.
- Developed the AngularJS application and implemented the HTML/CSS delivered by Erik Frisk, design/UX specialist.
- Developed filtering and sorting algorithms based on the requirements of the researchers.
Technologies: JavaScript, CSS, AngularJS, PhoneGap, Amazon S3 (AWS S3), Node.js, Agile Software Development, Extreme Programming, HTML5, Web Standards, Functional Programming, Object-oriented Programming (OOP), SCSS, Version Control, Mobile Web, Bootstrap, CSS3, HTML, HTTP, Git, Linux, Sass, Ajax, Lean Development, NoSQL, Express.js, Front-end, APIs, Responsive Design, Amazon Web Services (AWS), Single-page Applications (SPAs), Webpack, Full-stack, SaaS, Back-end, REST APIs, Cross-browser Compatibility, REST, User Interface (UI), Angular, Full-stack Development, Architecture, JSON, User Experience (UX), Cloud, Server Security, Front-end Development, Responsive Web Apps
JavaScript Developer
2013 - 2014
Computational and Structural Biotechnology Journal
- Contributed to OC Journals. OC Journals publish scientific research articles and review articles and communication after full peer review. I set up the AWS cloud-based infrastructure to increase performance and reduce costs.
- Developed an AngularJS web application originally hosted at Csbj.org.
- Implemented PDF.js from Mozilla, making the website plugin-free while loading PDFs faster than with Adobe Reader. This approach to displaying articles also avoids the manual work of transforming a PDF into an HTML document, saving time and money.
- Wrote a fast search and filtering feature, allowing users to filter on article type, journal, journal volume, and preprints and search through titles and authors.
Technologies: JavaScript, Node.js, AngularJS, MongoDB, Amazon EC2, Front-end, APIs, Amazon Web Services (AWS), Web Standards, Mobile Web, Single-page Applications (SPAs), Bootstrap, CSS, HTML, Webpack, Full-stack, Back-end, REST APIs, Cross-browser Compatibility, REST, User Interface (UI), Angular, Full-stack Development, Architecture, JSON, User Experience (UX), Cloud, Server Security, Front-end Development, Responsive Web Apps
JavaScript Developer
2013 - 2014
StockIt
- Contributed to StockIt, an online marketplace for international timber merchants. I created the MVP StockIt used to gain traction and compete with other startups at Chalmers Innovation. I set up an Amazon EC2 server to host the app and the StockIt API.
- Designed and set up the DynamoDB database and created a custom stock list designer, allowing users to easily copy stock lists and turn them into offers on the website.
- Implemented a real-time bidding system, including a permission model needed to protect bidders and gain market data.
Technologies: Node.js, Backbone.js, Amazon DynamoDB, JavaScript, Single-page Applications (SPAs), Bootstrap, CSS, Front-end, HTML, Express.js, Webpack, Full-stack, SaaS, Back-end, REST APIs, Cross-browser Compatibility, REST, User Interface (UI), Charts, Angular, Full-stack Development, Architecture, JSON, User Experience (UX), Cloud, Server Security, Front-end Development, Responsive Web Apps
JavaScript Developer
2013 - 2014
Francesco Gatto PhD
- Worked with Francesco Gatto, a Ph.D. student at Nielsen's Systems and Synthetic Biology group at the Department of Chemical and Biological Engineering. His research is on modeling cancer metabolic reprogramming using genome-scale metabolic networks.
- Created, together with my university project group, the Cancer Transcriptome Database, a restructured version of the Cancer Genome Atlas (TCGA) database to be more optimized for Francesco's research.
- Created a web GUI using AngularJS to explore the API we provided with the database.
Technologies: JavaScript, Node.js, MySQL, Single-page Applications (SPAs), Bootstrap, CSS, Front-end, HTML, Webpack, Full-stack, Back-end, REST APIs, Cross-browser Compatibility, REST, Data Visualization, User Interface (UI), Angular, Full-stack Development, Architecture, JSON, User Experience (UX), Front-end Development, Responsive Web Apps
JavaScript Developer
2012 - 2012
Aafje
- Created an entire app for Aafje, a social services foundation in need of a searchable and editable list of firms and services.
- Included an easy viewer-to-editor toggle feature, allowing all fields to be edited.
- Implemented a basic account system used for administrators of the app.
- Allowed the app to create backups of all data, which can be downloaded and saved on the server.
- Wrote the functionality allowing the list to be sorted, filtered, and searched through. The algorithm used allowed for misspellings of words.
Technologies: CSS, HTML, JavaScript, PHP, Single-page Applications (SPAs), Front-end, Node.js, Full-stack, Back-end, REST APIs, Cross-browser Compatibility, REST, CTO, User Interface (UI), UI Design, Full-stack Development, Architecture, JSON, User Experience (UX), Cloud, Server Security, Front-end Development, Responsive Web Apps
JavaScript Developer
2012 - 2012
Bullingdon Research Limited
- Worked on a data-visualization app for finance experts consisting of 27 pages and nine page types. Incorporated multiple HTML5 features to create an elegant design.
- Refactored the front-end JavaScript codebase to improve performance and simplify the code.
- Implemented a style makeover using PSD delivered by the lead designer. Created all templates by hand and did on-demand pixel fitting with the designer.
- Implemented CSS preprocessing, allowing the team to use the more elegant LESS language, reducing the codebase even more, and making future refactoring jobs easier.
- Built a cover page for marketing purposes with a price calculator and a video viewer using YouTube.
- Created a CSV uploader/editor/processor to be used when financial experts want to add custom data to their datasets.
Technologies: Node.js, Backbone.js, CSS, HTML, JavaScript, Ajax, Agile Software Development, Front-end, APIs, Responsive Design, Single-page Applications (SPAs), SaaS, REST APIs, Cross-browser Compatibility, REST, D3.js, Data Visualization, User Interface (UI), Charts, Artificial Intelligence (AI), Architecture, JSON, User Experience (UX), Cloud, Front-end Development, Responsive Web Apps
JavaScript Developer
2011 - 2012
Dutch Didit B.V.
- Created a prediction game with leaderboards, monthly prizes, score calculations, questions and answers, an accounting system, and support for multiple languages. This app was later sold to a leading Dutch newspaper.
- Wrote all HTML/CSS for both the mobile and desktop version of the app using the PSD given by the lead designer.
- Wrote all JavaScript and included support for multiple pages and integration of the HTML5 History API.
- Made the app compatible with IE8+ and all modern browsers.
- Connected the app with a back end API using Ajax with JSON.
Technologies: CSS, HTML, JavaScript, Single-page Applications (SPAs), Front-end, REST APIs, Cross-browser Compatibility, REST, User Interface (UI), JSON, User Experience (UX), Front-end Development, Responsive Web Apps
JavaScript Developer
2010 - 2010
Strait Solutions B.V.
- Contributed to Strait Solutions, a company that develops websites, designs, and campaigns for customers.
- Created the websites using custom markup code based on a design given by the lead designer.
- Implemented the company's website for customer onboarding.
- Added JavaScript widgets to a number of client websites.
- Built a custom interface based on the Blogger CMS.
Technologies: CSS, HTML, JavaScript, Front-end, Cross-browser Compatibility, User Interface (UI), JSON, User Experience (UX), Front-end Development
Experience
Esports Data Management for Riot Games
https://www.bayesesports.com/oddsBayes Esports works with Riot Games to provide data access management, real-time analysis, and AI/ML insights to tournament match data. I developed multiple applications, some of which also integrate data for Counter-Strike (for ESL) and Dota 2 (for Valve).
Mortgage and Insurance Calculation Tools
The National Mortgage Association in the Netherlands is part of the Holland Financial Business Group, providing tools to Dutch residents to help them save costs and estimate potential mortgage options. The project initially started with six different kinds of calculations, increasing to 21 over time.
Quantumplate
https://www.quantemplate.comQuantemplate is a SaaS platform that specializes in data integration, automation, validation, and analytics for the reinsurance and insurance industry. The platform automates the preparation and handling of insurance data and documents to help manage policy portfolios.
Education
2005 - 2011
High School Degree in Information Technology and Physics
Develstein College - Zwijndrecht, Netherlands
Certifications
SEPTEMBER 2009 - PRESENT
Typing Certificate
Develstein College
Skills
Libraries/APIs
Google API, Node.js, Backbone.js, React, REST APIs, Web3.js, React Redux, Stripe, D3.js, Puppeteer, Chart.js, ApexCharts.js, RxJS, AG Grid, WhatsApp API
Tools
Git, GitHub, Webpack, Stripe Checkout, Flash, Figma, ChatGPT, Sentry, Ganache
Languages
CSS, HTML, HTML5, CSS3, Sass, JavaScript, TypeScript, JavaScript 6, SQL, SCSS, ECMAScript (ES6), PHP, Python, GraphQL
Frameworks
Bootstrap, Express.js, Next.js, AngularJS, Tailwind CSS, Redux, Angular, Material UI, Svelte, PhoneGap, Cypress, Electron, NestJS
Paradigms
Object-oriented Programming (OOP), Functional Programming, Agile Software Development, Extreme Programming, REST, Unit Testing, UI Design
Platforms
Linux, Google Cloud Platform (GCP), Blockchain, Amazon EC2, Amazon Web Services (AWS), Firebase, Ethereum, Docker
Storage
MongoDB, NoSQL, MySQL, Amazon S3 (AWS S3), JSON, Firebase Realtime Database, Amazon DynamoDB, Google Cloud
Other
Ajax, Lean Development, Mobile Web, WebSockets, HTTP, Web Standards, Version Control, APIs, Front-end, Responsive Design, Single-page Applications (SPAs), Full-stack, SaaS, Back-end, Cross-browser Compatibility, Data Visualization, User Interface (UI), Charts, Full-stack Development, Architecture, Server Security, Cryptocurrency, User Experience (UX), Cloud, Front-end Development, Responsive Web Apps, Payment APIs, Web Components, Blockchain & Cryptocurrency, CTO, Artificial Intelligence (AI), LangChain, OpenAI GPT-4 API, Machine Learning, Chatbots, AI Tools, Learning Management Systems (LMS), Typing, Web Development, Publishing, Financial Services, Finance, eCommerce, Startups, Early-stage Startups, High-tech Startups, Large Language Models (LLMs), Lean Startups, Software as a Service (SaaS), Pinecone, OpenAI, Graphics, Component Libraries, Ethereum Virtual Machine (EVM), Ethers.js, WalletConnect, Web3, WhatsApp, WhatsApp Business
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