Senior UI Engineer for AI Platform & Visualizations

Mastercard; Tallaght; On-site; EUR 90,000 - 125,000; Full time

Job summary

Mastercard is seeking a Senior UI Developer to join an AI product team building foundation model capabilities with enterprise impact. You will design and develop frontend applications that translate complex model outputs into clear, interactive experiences for AI engineers and product teams.

You’ll own frontend layers across internal tooling and external self-service tools, ensuring scalable architecture, robust testing, and smooth integration with the platform’s API surface and Databricks

Qualifications

• Strong, production-level frontend development experience in React, and/or Python-based data-app frameworks (Streamlit or Dash).
• Component architecture, state management, and building applications meant to be maintained and extended over time, not one-off prototypes.
• Experience integrating frontend applications against REST APIs. Including handling authentication, asynchronous job patterns (submit, poll/callback, retrieve), and designing around API versioning.
• Familiarity with visualization libraries capable of advanced/interactive rendering (e.g., D3.js, deck.gl, Plotly, or similar).
• Familiarity with Databricks Apps as a hosting/deployment model, including its constraints and how it serves React, Streamlit, and Dash applications specifically. Direct Databricks experience is a strong plus.
• Advanced data visualization experience, including interactive/exploratory tooling. Not just static charts, but genuinely interactive interfaces: filtering, drill-down, dynamic re-rendering, and ideally experience visualizing high-dimensional or embedding-style data.
• Comfortable designing for mixed technical audiences. From AI engineers who want dense, fast access to detail, to end users who need simplicity and guardrails.
• Fluency reading/writing SQL or querying a governed data platform (e.g., Unity Catalog).
• Strong UI/UX instincts. Able to make reasonable design decisions independently rather than needing every interaction pattern specified, while knowing when to loop in design/product input.
• Solid testing and code quality practices for frontend code. Component/unit testing, and comfort working within CI/CD pipelines the rest of the team maintains.
• Clear communicator, able to work directly with backend, data, and AI engineering roles to understand what an interface actually needs to expose.
• Comfortable operating in a fast-moving, evolving environment.

Responsibilities

• Design and build advanced, interactive visualization tooling for embeddings and model outputs.
• Design and build self-service applications for end users.
• Design and build prototypes for future product versions and executive level demos.
• Design and build internal tooling for AI teams.
• Build and maintain applications on Databricks App hosting and integrate with Unity Catalog and APIs.
• Integrate frontend applications against the platform's API layer with backend teams.
• Collaborate with data and AI engineers on tooling requirements.
• Own frontend code quality, testing, and documentation.
• Design with a mixed audience in mind (technical and non-technical).
• Contribute to frontend architecture decisions and tooling.
• Support production issues spanning frontend and backend.

Skills

React frontend

Python data-apps

Component architecture

REST APIs

Data visualization

Databricks Apps

D3/Plotly/deck.gl

SQL

UI/UX instincts

Testing/CI/CD

Cross-functional collaboration

Tools

Databricks Apps hosting

Unity Catalog

Job description

Mastercard is seeking a Senior UI Developer to join an AI product team building foundation model capabilities with enterprise impact. You will design and develop frontend applications that translate complex model outputs into clear, interactive experiences for AI engineers and product teams.

You’ll own frontend layers across internal tooling and external self-service tools, ensuring scalable architecture, robust testing, and smooth integration with the platform’s API surface and Databricks