Site Reliability Engineer - Front-end React Specialist

Summary

Join ZILO™, a UK-based FinTech company specializing in global asset and wealth management software, and become a seasoned Site Reliability Engineer (SRE) with a front-end focus. You will ensure the reliability, performance, and operability of our React-based user interfaces. This role involves leading incident response for client-side issues, diagnosing end-to-end failures, and building automation tools. You will also design and operate Kubernetes clusters, manage AWS infrastructure, and optimize React application performance. Collaboration with various teams and knowledge sharing are key aspects of this position. ZILO™ offers a dynamic and inclusive work environment with opportunities for continuous learning and growth.

Responsibilities

• Act as primary on-call for React application incidents: crashes, memory leaks, performance regressions, or deployment failures
• Analyze browser logs, application metrics (e.g. Real User Monitoring), and backend traces to isolate root causes across React , Node.js services, AWS , and Kubernetes layers
• Orchestrate post-incident reviews: document findings, define mitigation plans, and drive tickets to resolution
• Develop and maintain robust observability for front-end components: integrate Datadog for obervability
• Define SLIs/SLOs for page load times, Time to Interactive, and error rates; build alerting that balances sensitivity with noise reduction
• Automate deployments via CI/CD pipelines (GitHub Actions), including end-to-end tests, canary releases, and rollbacks for React apps
• Design and operate Kubernetes (EKS) clusters hosting Node.js microservices and SSR/Next.js rendering tiers
• Implement auto-scaling policies and ensure blue/green or rolling updates minimize user disruption
• Manage AWS infrastructure (EC2, ALB, CloudFront, S3) to optimize content delivery and reliability of front-end assets
• Profile and tune React applications: code-splitting, lazy loading components, optimizing bundle sizes, and minimizing hydration times
• Leverage caching strategies (CDN invalidation, HTTP caching headers) to reduce latency and origin load
• Collaborate with UX teams to balance feature richness with performance targets
• Serve as the React/SRE subject-matter expert: mentor engineers on best practices for building resilient front-ends
• Produce and maintain runbooks, debugging guides, and incident-playbooks specific to client-side failures
• Partner closely with wider backend SRE, DevOps, and product teams to ensure end-to-end reliability

Benefits

• Enhanced leave - 38 days inclusive of 8 UK Public Holidays
• Private Health Care including family cover
• Life Assurance – 5x salary
• Flexible working-work from home and/or in our London Office
• Employee Assistance Program
• Company Pension (Salary Sacrifice options available)
• Access to training and development
• Buy and Sell holiday scheme
• The opportunity for “work from anywhere/global mobility”