A focused timeline of roles, responsibilities, and the technologies I used to deliver impact.

Focus
What I care about
Product UIDesign systemsPerformanceMotion polish
Toolbox
Daily drivers
ReactTypeScriptNext.jsJavaVitestFigma
Software Engineer

Nederlandse Spoorwegen - Agile Release Team (Koplopers team)

May 2025 - PresentDen Haag, NL

At Nederlandse Spoorwegen, I am part of the Agile Release Team in the Koplopers team. We develop and maintain the platform responsible for train equipment adjustment — helping planners manage train assignments and movements efficiently. As a Software Engineer, I focus on delivering performant, interactive user interfaces that enable fast and intuitive workflows. I collaborate closely with UX designers, back-end developers, and domain experts to ensure seamless integration and usability.

Technologies

    ReactViteTypeScriptJavaVisxJavaScriptHTMLCSSSCSSStyled ComponentsSWRStoryBookJestCypress

Contributions

  • Building scalable and performant interfaces using React.js and TypeScript.
  • Implementing responsive and dynamic UI with SCSS/CSS Modules and Framer Motion.
  • Efficient client-side data management using Tanstack Query.
  • Mocking APIs and simulating edge cases with MSW for frontend development.
  • Writing robust unit and end-to-end tests using Vitest and Playwright.
  • Creating interactive and performant visualizations using Visx (Airbnb).
Software Engineer

NS Stations - OV Fiets

Feb 2023 - May 2025Den Haag, NL

At NS Stations - OV Fiets, I work on FRAME, the OV-Fiets platform. As the sole Software Engineer on the team, I am responsible for designing and implementing user-friendly web interfaces. Together with the UX designer, we aim for better design and optimal user experience. I collaborate closely with backend developers and ensure front-to-back connectivity via NS APIs. I also write unit tests with Jest and end-to-end tests with Cypress. We follow SCRUM and Agile methodologies with 3-week sprints.

Technologies

    ReactTypeScriptJavaScriptHTMLCSSSCSSStyled ComponentsSWRStoryBookJestCypress

Contributions

  • Developing dynamic and interactive web applications.
  • Creating responsive and visually appealing designs.
  • Efficient data fetching in React.
  • Developing and testing UI components in isolation.
  • Writing unit tests and end-to-end tests to ensure code quality.
ServiceNow Engineer

ServiceNow engagements: Capgemini · Philips · Roche · ABN AMRO · Lamb Weston

Nov 2018 - Feb 2023Den Haag, NL

Led front-end development for ServiceNow implementations across multiple enterprise clients. Built Now Experience UI, portals, and catalog workflows, improved service delivery with IT4IT-focused enhancements, and shipped integrations with external systems.

Technologies

    ServiceNOWAngularJSJavaScriptHTMLCSSRESTSOAP-UI

Contributions

  • Built ServiceNow portals and Now Experience UI with AngularJS, JavaScript, HTML, and CSS.
  • Implemented catalog workflows, case scenarios, and platform features aligned with ServiceNow best practices.
  • Integrated external systems via REST/SOAP APIs and platform packages (including Nexthink).
  • Collaborated in Agile/SCRUM teams to deliver iterative UX improvements.
Software Engineer

PalmeraBytes (Team)

Jun 2017 - 2021Den Haag, NL

PalmeraBytes was a group of friends who built applications together and helped each other grow as engineers. At PalmeraBytes, I worked on various projects with ReactJs, NodeJs, TypeScript, ExpressJs, MongoDB (Mongoose), and GatsbyJS. I was responsible for frontend development and learned to set up Docker-based development environments.

Technologies

    ReactNode JsTypeScriptExpressJsMongoDB (Mongoose)GatsbyJS

Contributions

  • Developing dynamic and interactive web applications.
  • Working iteratively and flexibly with SCRUM & Agile.
  • Tools: JIRA, Confluence, Slack, Gitlab, Git, Github.

Let’s build something great.

Open to frontend roles, product collaborations, and high‑impact teams.

© 2026Andres Haayen