Javascript Developer

Helyx
London
2 months ago
Applications closed

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Mid to Senior-Level React Engineer – GIS & Esri JS API

Are you a skilledReact Engineerwith a passion forgeospatial technologies? Do you thrive in dynamic environments where precision and innovation are crucial? JoinHelyxand be part of a team delivering cutting-edge solutions fordefence and securityapplications.


Role Overview

We are seeking an experiencedReact Developerwith expertise in GIS and theEsri JavaScript APIto build, optimise, and maintain interactive web applications for our defence and security clients. Your role will involve working with complex geospatial datasets, integrating with mapping services, and creating intuitive user experiences that enhance operational efficiency and situational awareness.


Key Responsibilities

  • Develop and maintain interactiveGIS-based web applicationsusingReact.
  • Design and implement scalable, high-performance front-end architectures for mapping solutions.
  • Work closely with geospatial analysts and backend developers to deliver seamless applications.
  • Integrate geospatial data sources and RESTful APIs to visualise and manipulate data in real-time.
  • Optimise application performance and ensure compatibility across different browsers and devices.
  • Troubleshoot and resolve issues related to geospatial data rendering and interactivity.
  • Contribute to the adoption of best practices inmodern front-end development.
  • Maintain high standards of security, performance, and usability in all projects.


What You Bring to the Table

  • Strong proficiency in React.js, including hooks, component lifecycle, and performance optimisation.
  • Solid understanding ofJavaScript (ES6+), TypeScript, and modern front-end tooling.
  • Familiarity withGIS data formats (GeoJSON, WMS, WFS, KML, etc.)and working withgeospatial databases.
  • Experience ofRESTful APIdevelopment.
  • Exposure tomapping librariessuch as Arcpy, Leaflet, OpenLayers, or Mapbox is beneficial.
  • Strong problem-solving skills and the ability to work in a fast-paced, agile environment.
  • UK Security Clearance (or eligibility to obtainDeveloped Vettingfor sensitive projects – UK Nationals only).


Nice to Have

  • Experience with theArcGIS API for JavaScript.
  • Experience integrating with ArcGIS services such asArcGIS Enterprise.
  • Knowledge of graph computing frameworks such asNetworkXorSigmaJS.
  • Understanding of building and or exploiting machine learning models.
  • Software design or architecture experience.
  • Leadership or mentoring experience.
  • Familiarity with backend technologies such asPython, FastAPIand relational databases.
  • Cloud deployment experience (AWS, Azure, or GCP).


Location

This role is home based with occasional need to travel to the Helyx office in Twyning and to client sites around the UK.


What's in It for You?

  • Competitive salarybased on experience.
  • Generous bonus incentivesrecognising contributions.
  • 9% pension plan,healthcare coverage, andlife cover.
  • 10 days per year for professional development(5 formal training days + 5 personal development days).
  • Salary Sacrifice ULEV car scheme– promoting sustainability.
  • Wellbeing allowanceto support your physical and mental health.
  • A commitment to ongoing learning and career development.

Join Us!

If you're aReact Engineer passionate about GIS, eager to work on impactful projects, and looking for an opportunity to shape the future of defence and security technologies, apply today!


Next Steps

Express your interest onLinkedInor or contact our recruitment team at


Helyx is anequal opportunities employer.


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