Frontend/UI Engineer (Junior to Mid-Level)
Company Description
Craxel is reshaping the future of data analytics and artificial intelligence through its breakthrough Black ForestTM technology, a knowledge infrastructure designed for AI-powered decision making at any scale. Black Forest provides instant access to fully connected, multidimensional data for both human and machine intelligence, enabling contextualization of highly complex datasets across trillions of records and relationships. Powered by a novel O(1) indexing engine, Craxel delivers low-latency, high-performance results with significant price efficiency, regardless of data size. By consolidating fragmented data into AI-ready knowledge graphs, Craxel supports faster, more informed decisions in domains such as national security and financial intelligence.
Role Description
As a Frontend Engineer (Junior to Mid-Level) at Craxel, you will design, build, and maintain our core back end product and user interface that enable users to interact effectively with complex data and AI-driven insights. You will implement responsive, accessible web frameworks, collaborate with users and backend engineers to integrate APIs, and ensure high performance and reliability across modern browsers and devices. Your daily responsibilities will include writing clean, testable code, participating in code reviews, resolving UI/UX issues, and contributing to the continuous improvement of frontend tooling and workflows add new features and new visualisation libraries. This is a full-time, role based in Belfast, with a mix of on-site (2 days a week minimum) and work-from-home.
What You Will Work On
- Designing and Developing our next generation UI
- Integration of new libraries and tools
- REST API integration agains our Black Forest query end points, config, and data endpoints
- Data exploration UI enhancements including: new charts, geo maps, time-series, tabular query results
- Complex form design and validation: nested config forms, credential inputs
- Async operation handling: service start-up feedback, connection testing, error states
- Unit and component testing
- Evolving the UI as BFKI APIs and capabilities expand
Must Have
2+ Years experience in a relevant role
Languages and Frameworks
- JavaScript/TypeScript
- HTML
- CSS
API Integration
- Experience with REST
- Understanding of query construction and result rendering from API responses
UI Patterns
- Complex form design and validation
- Ability to develop fully interactive UI components
- Role-aware UI patterns (permission-based rendering, route guards)
- Async operation handling and error state management
Data Vocabulary
- Familiarity with common visualization types: geo maps, time series, pie/bar/line charts, tabular data
- Ability to translate customer data requirements into appropriate frontend implementation
General
Git, GitHub Actions, Agile, Jira
Good to Know
- Modern Framework Experience
- React, Angular
- Modern Library Experience
- D3.js, Chart.js
- Modern UI Design Patterns
- WebSocket experience
- UX/CX design (e.g. Figma)
- OpenTelemetry
- Testing Framework Experience
- Unit: Jest
- E2E:Selenium, Playwright, Cypress
- Experience designing for WCAG compliance
- AWS or GCP
Bonus Points
Public GitHub with meaningful frontend contributions
Technical blog posts, conference talks, or published writing on data visualization or frontend architecture
What we offer
- A competitive salary and bonus plan
- A competitive salary depending on experience
- 25 days holidays plus 10 UK public holidays
- Private medical insurance including family cover, Dental and Optical
- 5% employer-matched pension to invest in your future
- Death in service cover and income protection
- Personal and business travel insurance
- A dedicated training and development allowance
- A health and well-being allowance to support life inside and outside of work
- Hybrid working, with flexibility