Summary
✨ AI‑Generated
Take technical ownership of several business-critical internal web applications in a hybrid engineering role. Working close to the browser with Vanilla JavaScript, HTML, and CSS, you will maintain and enhance existing systems, resolve performance and technical debt issues, and build new functionality from business requirements.
Highlights
Hybrid application engineering role with ownership of business-critical internal web applications, combining hands-on development with long-term responsibility for performance, reliability, maintainability, and feature delivery.
Description
Location: Central London (Hybrid, 3 days onsite)
Salary: Up to £40,000
Our client is looking for an Application Engineer to take ownership of a suite of business-critical internal web applications.
This isn't a traditional Front End Developer role.
They're looking for an engineer who enjoys solving complex technical problems, working close to the browser using Vanilla JavaScript, HTML and CSS, and taking long-term ownership of existing applications.
Working alongside the Head of Digital Transformation & Change and a Senior Developer, you'll become the technical owner of three core internal applications, maintaining, enhancing and evolving the platforms while ensuring they remain performant, reliable and easy to use.
Responsibilities
Take ownership of three business-critical internal web applications.Maintain, enhance and support existing functionality, resolving bugs, performance issues and technical debt.Design and implement new features based on business requirements and user feedback.Build and maintain complex, data-driven user interfaces using Vanilla JavaScript, HTML and CSS.Work on authenticated, multi-user business applications, ensuring reliability, performance and scalability.Continuously improve usability, accessibility and overall user experience.Prepare the applications for international expansion, including localisation, translations and jurisdiction-specific workflows.Collaborate closely with business stakeholders to deliver practical, user-focused solutions.Leverage AI-assisted development tools as part of your day-to-day engineering workflow.
Technical Skills
Essential
Experience using AI-assisted development tools to improve engineering productivity is essential.Strong commercial experience with Vanilla JavaScript, HTML and CSS.Experience owning and maintaining complex web applications.Strong understanding of application architecture, state management and performance optimisation.Experience working with authenticated, multi-user business applications.Excellent debugging and problem-solving skills.Comfortable working closely with non-technical stakeholders.
Desirable
Experience with authentication, RBAC or permission-based systems.Experience with caching, automated testing and performance optimisation.Exposure to localisation or internationalisation.Experience building browser extensions, plugins or other cross-platform interfaces.
What We're Looking For
Our client is looking for someone who enjoys taking ownership of established applications and solving complex engineering challenges without relying on modern frontend frameworks.
This role would suit someone who is comfortable working directly with the browser, writing clean, maintainable Vanilla JavaScript and continuously improving business-critical systems used by teams across the organisation.
Candidates with experience building and owning complex, authenticated applications, coupled with a passion for AI-assisted development, will be particularly well suited to this opportunity.
Tech Stack
Vanilla JavaScriptHTMLCSS
