UI Engineer (Junior to Mid-Level)

Company Description

Craxel is at the forefront of innovation in data analytics and artificial intelligence. Our revolutionary Black ForestTM technology provides an advanced knowledge infrastructure that enables AI-driven decision-making at any scale with unmatched speed and efficiency. By consolidating vast, complex, and fragmented datasets into AI-ready knowledge graphs, Black Forest empowers organisations to gain instant, actionable insights. From national security to financial intelligence, Craxel delivers transformative solutions for data-driven decision-making.

Role Description

We are seeking a Frontend Developer for a full-time hybrid role based in Belfast, with flexibility for some remote work. In this role, you will build and maintain the UI to our Black ForestTM data platform, you will also be responsible for the design and implementation of user interfaces for web applications, ensuring a seamless user experience. Day-to-day responsibilities include developing responsive web designs, collaborating with back-end developers to integrate APIs, and enhancing application performance. You will contribute to building scalable and innovative web solutions while working within a collaborative and fast-paced environment.

What You Will Work On

• REST API integration against BFKI query, config, and data endpoints
• Data exploration UI: 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
• 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 implementations

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
• Salary ranging from £40-50k depending on experience
• 25 days holidays plus 9 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