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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Frontend Engineer - **Company:** Plentific - **Location:** London, United Kingdom (Remote available) - **Experience:** Expert - **Salary:** £71,608 - **Contract:** Permanent contract - **Skills:** JavaScript (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Software as a Service, Code Generation, Code Review, Cross-Site Request Forgery, Cursor, Software Debugging, Software Design Patterns, Django Web Framework, Github, Routing, Pair Programming, E2e Testing, Service-Oriented Architecture, Software Engineering, TypeScript, Web Applications, Network Routers, ReactJS, Claude Code, Grafana, AI Coding Agents, Cross-Site Scripting (XSS), Backend, Agentic-AI, Material UI, Sentry, Front End Software Development, Restful APIs, Code Restructuring, New Relic (SaaS) - **Published:** November 12, 2026 - **Apply:** https://www.adzuna.co.uk/jobs/details/5962868147 ## About the Role * Expert-level TypeScript and modern JavaScript, with deep command of React and the patterns around it, including data fetching, routing, and component libraries. * Strong software engineering fundamentals, including design patterns, testing, debugging, and code that stays readable and extendable at scale. * Sound grasp of UI, UX and accessibility considerations, with the judgement to improve a design before building it rather than implement it exactly as drawn. * Demonstrable experience diagnosing and fixing page load, rendering, and other frontend performance problems. * Working knowledge of frontend observability with Sentry, Grafana logs, or New Relic, and of CI/CD pipelines such as GitHub Actions or ArgoCD. * Practical awareness of common frontend security risks, including XSS and CSRF, and how to design against them. * Strong working fluency with agentic coding tools and spec-driven development workflows, including specification writing, code generation, test generation, and critical review. * Clear communication, with the ability to articulate technical concepts and trade-offs in plain English. * High ambition and a strong sense of urgency, with the drive to deliver an ambitious product roadmap at pace using AI, and a positive, can-do attitude. * 6+ years of professional software engineering experience, including 5+ years of commercial React and TypeScript. * Experience shipping and operating production frontends for customer-facing SaaS products, including monitoring, incident response, and performance improvement. * Experience working in a large, long-lived codebase where design patterns, testability, and maintainability genuinely matter. * Experience consuming and shaping REST APIs in a service-oriented architecture, ideally backed by Django REST Framework or an equivalent. * Experience working in cross-functional teams with product managers and designers on shared customer outcomes, not only technical delivery. * Experience using AI coding tools in a professional software delivery workflow, ideally within a spec-driven development framework. ## Description * Build and maintain product interfaces in TypeScript, React, TanStack Query, React Router, MaterialUI and BaseUI across our web applications. * Translate product requirements and design concepts into technical documents that set out scope, system behaviour, edge cases, and high-level technical analysis. * Design component APIs, state management, and data-fetching patterns that stay readable and extendable as the codebase grows. * Integrate against REST APIs in a service-oriented architecture, shaping the contracts with backend engineers rather than accepting whatever is offered. * Review, refactor, and retire existing code so it meets the requirements of improved or new features. Performance, Quality, and Reliability * Diagnose and resolve page load, rendering, and other frontend performance problems. * Write unit, integration, and end-to-end tests that give the team confidence to ship frequently. * Instrument frontend observability with tools such as Sentry, Grafana Logs or New Relic, and act on what they show. * Debug and fix production issues across our applications, including the integration points where frontend and backend behaviour diverge. * Design against common frontend security risks, including XSS and CSRF. Agentic and Spec-Driven Development * Turn ambiguous product ideas into implementation-ready specs, including user flows, component behaviour, edge cases, acceptance criteria, and test expectations. * Prototype interfaces and interaction quickly, using working software to test feasibility and product value before committing to larger delivery. * Use agentic coding tools such as Codex, Claude Code, Cursor, or equivalent to generate, refactor, test, and review code within clear technical constraints. * Evaluate AI-generated code critically for correctness, maintainability, security, performance, accessibility, and fit with Plentific's architecture. * Improve the team's spec-driven development practice through reusable prompt patterns, review checklists, examples, and lightweight documentation. Collaboration and Craft * Partner with product managers, designers, and backend engineers from problem framing through release, applying engineering judgement to improve the user experience before implementation starts. * Collaborate with other engineers through code review and pair programming. * Define and communicate frontend standards and best practice, and hold the team to them in review. * Write concise technical documentation covering components, algorithms, APIs, and operational handover. * Articulate technical trade-offs in plain English to technical and non-technical colleagues, including when scope, quality, or delivery timing needs to change.