Senior / Principal Frontend EngineerOcho People | Technology RecruitmentSenior / Principal-level frontend engineering role at a fast-growing AI and cloud software scaleupReact and TypeScript focused with a modern, well-considered stackMission-critical product used by law enforcement and security organisations worldwideHybrid working with a Belfast baseSalary up to £85,000About the CompanyOur client is an advanced body camera and cloud software scaleup working with some of the biggest names in security, services and law enforcement. They build AI-driven video forensic and evidence analysis tooling that genuinely matters, technology that helps keep people safe and supports complex investigative workflows at scale. The culture is open, transparent and collaborative, with a strong one-team ethos and a real sense of shared purpose. This is a company that invests in its people and takes pride in doing meaningful work.The RoleThis is a hands-on Senior or Principal Frontend Engineer position at the heart of the product engineering team. You will help shape the user experience behind complex investigative workflows, video review, transcription, timeline analysis, streaming and AI-assisted insights, building fast, reliable and intuitive interfaces for large-scale, media-heavy applications. Working closely with backend engineers, product and design, you will deliver modern React applications that balance performance, usability and maintainability across mission-critical workflows. The level of the appointment will reflect your experience and the contribution you can make from day one.Key ResponsibilitiesBuild and maintain React applications using TypeScript, Tanstack Router and Query, and Shadcn UIDesign type-safe APIs with tRPC spanning frontend and backend systemsDevelop AWS Lambda functions and manage infrastructure with AWS CDKWork across React (Vite) and monorepos using Turbo and pnpmWrite automated tests with Vitest and PlaywrightOptimise performance across bundle sizes, Core Web Vitals and query cachingReview code, maintain strict TypeScript standards and ensure security best practices with Zod validationCollaborate with backend engineers, product managers and designers to deliver high-quality softwareTake ownership of features from requirements through to productionWhat You'll NeedEssential:5 or more years of professional TypeScript and JavaScript developmentExpert-level React with modern patterns across SPA applicationsStrong experience with modern build tools such as Vite, Turbo and webpackSolid monorepo management experienceA pragmatic approach to engineering - you value simplicity, type safety and clarityNice to Have:Experience with tRPC and the Tanstack ecosystem (Query, Router, Table) and AWS CDK exposureTailwind CSS and Shadcn or Radix component librariesZod validation and Playwright end-to-end testingPerformance optimisation and Web Vitals experienceReact NativeWhy Apply?Salary up to £85,000 depending on experienceHybrid working with a Belfast city centre baseGenuinely impactful work, technology used by law enforcement and security organisations globallyGenerous annual leave allowancePrivate health insurancePension matching schemeLearning and development opportunities with real room to growCycle to work scheme and Home and Tech Scheme through salary sacrificeA collaborative, inclusive culture where diverse teams are celebrated, and everyone can thriveHow to ApplyKeen to find out more? Connect with Nick Napier on LinkedIn or submit your CV via the link below for a confidential conversation about this opportunity.Benefits:Work From HomeWHJS1_NI