Frontend (UI) Engineer, Email Security

At Cloudflare, we are on a mission to help build a better Internet. Today the company runs one of the world's largest networks that powers millions of websites and other Internet properties for customers ranging from individual bloggers to SMBs to Fortune 500 companies. Cloudflare protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code. Internet properties powered by Cloudflare all have web traffic routed through its intelligent global network, which gets smarter with every request. As a result, they see significant improvement in performance and a decrease in spam and other attacks. Cloudflare was named to Entrepreneur Magazine's Top Company Cultures list and ranked among the World's Most Innovative Companies by Fast Company. We realize people do not fit into neat boxes. We are looking for curious and empathetic individuals who are committed to developing themselves and learning new skills, and we are ready to help you do that. We cannot complete our mission without building a diverse and inclusive team. We hire the best people based on an evaluation of their potential and support them throughout their time at Cloudflare. Come join us! Available Locations: Lisbon, Portugal About the Department The Email Security - Applications team builds and runs the UI platform customers with email protection use to onboard, analyze, investigate, and remediate. We also build and run the internal tools, platforms, and APIs that run that software. Individual engineering teams are typically responsible for large areas with considerable impact, and able to execute autonomously within that space to deliver value to their customers - be they internal or external. About the Role We are seeking a skilled Frontend (UI) Engineer to join the Email Security - Applications team. The ideal candidates will have experience working with large-scale applications and a track record of producing great output. You must care deeply not only about the quality of your and the team's code, but also the customer experience. In this role, you will enhance UI infrastructure, streamline UX workflows, and collaborate across teams to improve code quality and developer velocity. Your contributions will be pivotal in refining the developer experience, ensuring high-quality frontend delivery, and optimizing performance and reliability at scale. We believe that a great design and simple UX is at the heart of any successful product, and you will work closely with our design/UX team and must be comfortable seeking feedback from non-technical sources. We work iteratively and deploy often. We're also strong believers in dog-fooding our own products. From Cloudflare Access to Cloudflare Workers and KV and R2 - these are all tools in our frontend engineer's tool belt. Key Responsibilities Help build and scale the Email Security platform frameworks. Drive UI infrastructure excellence, including CI/CD, observability, and experimentation tools. Tackle cross-cutting concerns to enhance developer velocity, maintainability, and code quality. Upgrade and maintain the frontend codebase, modernizing legacy components to align with current best practices. Collaborate with product and design teams to deliver cohesive, self-serviceable user experiences. Technologies We Use React, TypeScript, JavaScript (ES6+), Cypress, Vite, Webpack, CI/CD tools, RESTful APIs Qualifications We want someone who understands and obsesses over front-end systems. Experience designing, developing, and deploying M365 or Gmail Add-Ins a big plus. Passion for improving developer experience and increasing development velocity. 4+ years of experience in frontend engineering, specializing in JavaScript, TypeScript, and React. Strong knowledge of UI infrastructure, CI/CD, and testing frameworks (e.g., Playwright, Cypress). Proven ability to drive projects independently, from concept to implementation. Preferred Skills: Expertise in React, TypeScript, and modern front-end systems. Expertise in performance optimization for frontend applications. Experience with modern JavaScript bundling tools like Webpack or Vite. Familiarity with RESTful APIs. Experience building and maintaining integration test suites with API mocks. Experience building and scaling large-scale web applications.

Cloudflare is on a mission to help build a better Internet. The company runs one of the world's largest networks that powers millions of websites and other Internet properties for customers ranging from individual bloggers to SMBs to Fortune 500 companies. Cloudflare protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code.