Senior Frontend Systems Engineer - Hybrid Lisbon (1-3 Days/Week)

ABOUT THE OPPORTUNITY

Join the Portugal engineering team of an AI- and automation-driven financial crime operations company headquartered in Iceland, and help transform how financial institutions fight financial crime through cutting-edge technology. 

You'll be joining a growing engineering group of ~15 experienced engineers currently in an expansion phase, working on the technological core of operational transformation in financial crime prevention. This isn't traditional frontend development - you'll be building complex, real-time interfaces for AML investigations and case handling, working with large-scale data-driven UI systems that support investigators analyzing millions of transactions and making critical compliance decisions.

The company is moving beyond software-as-a-tool toward delivering automation, intelligent agents, and operational outcomes including agentic AI systems that support case decisions, precomputed analytics and detection engines, workflow automation, and human-in-the-loop intelligence that reduces manual workload. Your frontend work will be the critical interface layer enabling this transformation, requiring deep technical sophistication to handle real-time data, complex workflows, and high-performance requirements.

This role emphasizes engineering fundamentals over narrow specialization - the company seeks versatile senior engineers capable of adapting to evolving technologies and handling complexity across multiple domains. The engineering culture is anchored in design-first principles with rigorous architectural documentation through design docs, RFCs, and structured debates before implementation, ensuring transparency and consistency across the platform. You'll be expected to think at the system level, not just about UI components in isolation.

PROJECT & CONTEXT

You'll be building production-grade frontend systems for AML investigation platforms where performance, reliability, and user experience directly impact how financial institutions detect and prevent money laundering, terrorist financing, and other financial crimes. These aren't simple CRUD interfaces - you're creating complex, data-intensive UIs that help compliance officers navigate vast amounts of transaction data, customer profiles, risk indicators, and case evidence in real-time.

The technical environment requires senior-level React and TypeScript expertise applied to large-scale challenges - handling high-volume data rendering, managing complex application state across real-time updates, optimizing performance for data-heavy visualizations, and building sophisticated interaction patterns that support investigative workflows. You'll work with large-scale data-driven UI systems where understanding performance implications and making smart architectural decisions is critical.

Close collaboration with backend engineers is essential - you need to understand system behavior beyond just consuming APIs. You'll participate in discussions about data models, API contracts, caching strategies, and real-time data synchronization, ensuring frontend and backend work together efficiently. This requires system-level thinking about how components interact across data, compute, and operations layers, not just implementing mockups.

Your work must demonstrate strong UX sensibility combined with technical rigor - balancing sophisticated functionality with intuitive interfaces that help investigators work efficiently under time pressure. Experience with real-time UI patterns is critical as you'll handle live data updates, websockets, optimistic updates, and conflict resolution in collaborative investigation environments where multiple users may work on the same cases.

The company's design-first culture means you'll contribute to architectural discussions through design documents and RFCs before implementation, documenting frontend architectural decisions, debating trade-offs with the engineering team, and ensuring your solutions are reliable, maintainable, and operate predictably under real-world conditions. This isn't a "move fast and break things" environment - it's about building production systems with measured pragmatism, choosing technologies that solve real problems rather than adopting tools for their own sake.

Working within an Azure-native platform, you'll likely interact with services like AKS (Azure Kubernetes Service) for deployment, potentially work with data from systems using Spark, Iceberg, Trino, understand caching strategies with Redis, handle authentication through Keycloak, and ensure your frontend integrates seamlessly with distributed, event-driven backend systems. The company values engineers who can think conceptually, adapt quickly, learn new tools, navigate multiple environments, and create reliable systems rather than just specialists in specific frameworks.

Core Tech Stack: React (primary frontend framework), TypeScript (strict typing for large codebases), Azure (cloud platform)
Additional Context: AKS, Spark, Iceberg, Trino, Redis, Keycloak (backend/platform technologies you'll interact with)
Architecture: Distributed systems, event-driven, microservices, cloud-native
Domain: Financial crime prevention, AML operations, compliance investigations
Scale: Large-scale data processing, real-time updates, high-performance requirements

WHAT WE'RE LOOKING FOR (Required)

• Senior React Expertise: Senior-level React expertise with deep understanding of React architecture, performance optimization, advanced patterns, and large-scale application development
• TypeScript Mastery: Senior-level TypeScript proficiency including advanced typing, generics, type inference, and using TypeScript to build maintainable, type-safe large codebases
• Large-Scale Data-Driven UI: Experience building large-scale data-driven UI systems that handle high volumes of data, complex state management, and performance optimization
• System-Level Thinking: Understanding of system-level thinking - how frontend components interact with backend services, data pipelines, and distributed systems beyond just consuming APIs
• Backend Collaboration: Ability to collaborate closely with backend engineers on system behavior, API design, data contracts, and architectural decisions
• Real-Time UI Patterns: Experience with real-time UI patterns including websockets, live data updates, optimistic updates, conflict resolution, and collaborative editing
• UX Sensibility: Strong UX sensibility with ability to balance sophisticated functionality with intuitive interfaces for complex workflows
• Performance Reasoning: Ability to reason mathematically about performance - understanding computational complexity, rendering optimization, and making data-driven decisions about UI architecture
• Design-First Culture: Comfort working in design-first culture with architectural documentation, RFCs, and structured technical debates before implementation
• Reliability & Maintainability: Focus on designing systems that operate predictably under real-world conditions with emphasis on long-term maintainability
• Architectural Ownership: Architectural ownership mindset - taking responsibility for frontend architecture decisions and their long-term implications
• Measured Pragmatism: Measured pragmatism in technology choices - selecting tools that solve real problems rather than chasing trends
• Ownership & Accountability: Ownership and accountability for outcomes across design, implementation, and operations
• Strong Problem-Solving: Strong problem-solving skills for complex technical challenges in distributed, data-intensive environments
• Production-Grade Engineering: Experience building production-grade systems that operate at scale with proper error handling, monitoring, and operational awareness
• Language: B2+ English level (Upper Intermediate minimum) for technical discussions, documentation, and international team collaboration
• Location: Based in or willing to relocate to Lisbon with availability for hybrid work (1-3 days on-site per week)

NICE TO HAVE (Preferred)

• Distributed Systems Understanding: Deep understanding of distributed computation and how frontend fits into distributed system architectures
• Cloud-Native Architecture: Experience working within cloud-native architectures and understanding of how cloud infrastructure impacts frontend design
• Azure Ecosystem: Hands-on experience with Azure services and deployment on AKS (Azure Kubernetes Service)
• Event-Driven Systems: Understanding of event-driven and message-oriented systems and how to build UIs that integrate with these patterns
• Data Visualization: Advanced data visualization expertise for complex analytical interfaces (D3.js, Recharts, custom visualizations)
• Performance Engineering: Deep performance engineering skills including profiling, optimization techniques, and understanding browser internals
• State Management Advanced: Expertise with advanced state management patterns and libraries beyond basic Redux/Context (Zustand, Jotai, Recoil, XState)
• API Design: Understanding of production-grade API design and ability to contribute to API contract discussions
• Debugging Complex Systems: Experience debugging real-world systems across frontend and backend with operational awareness
• Multiple Tech Stacks: Ability to work across multiple technology stacks - not limited to just React ecosystem
• Financial Services/Fintech: Previous experience in banking, fintech, or financial services with understanding of compliance and regulatory requirements
• AML/Compliance Domain: Specific experience with AML (Anti-Money Laundering), compliance systems, or financial crime prevention
• Data-Heavy Applications: Track record building data-intensive applications (dashboards, analytics tools, investigation platforms)
• Collaborative Workflows: Experience building collaborative, multi-user interfaces with real-time synchronization
• Authentication/Authorization: Understanding of complex auth systems (OIDC, OAuth, role-based access control) particularly with Keycloak
• Micro-frontend Architecture: Experience with micro-frontend architectures for large-scale applications
• GraphQL: Experience with GraphQL for efficient data fetching in complex UIs
• Testing Strategies: Comprehensive testing expertise - unit, integration, E2E testing for frontend systems (Jest, React Testing Library, Cypress, Playwright)
• Accessibility: Strong accessibility practices (WCAG) for building inclusive interfaces
• Design Systems: Experience building or contributing to design systems and component libraries
• CI/CD for Frontend: Understanding of CI/CD pipelines specifically for frontend deployment and testing
• Monitoring & Observability: Experience with frontend monitoring and observability (error tracking, performance monitoring, user analytics)
• Technical Writing: Strong documentation skills for architectural decisions, component APIs, and system design
• Mentoring: Experience mentoring engineers and elevating team capabilities

Location: Lisbon, Portugal (Hybrid - 1-3 days on-site/week, exact days flexible)