# Marni Brewster > Senior Software Engineer at AllTrails Location: Philadelphia, Pennsylvania, United States Profile: https://flows.cv/marni Senior Software Engineer | Front-End Expert Specializing in React, Next.js, and TypeScript As a dedicated Senior Software Engineer, I bring a wealth of experience in front-end technologies, including React, Next.js (Next), and TypeScript, to create seamless and scalable web applications. My approach is grounded in a commitment to clean code, adherence to best practices, and a passion for innovative user experiences. With a strong foundation in modern JavaScript frameworks, I excel at designing and implementing responsive, high-performance web interfaces. My career is characterized by a focused expertise in the dynamic landscape of front-end development, ensuring that all projects I lead are not only functional but also visually appealing and user-friendly. I thrive in environments that value agile methodologies, robust leadership, and a culture that prioritizes feedback and continuous improvement. Known for my ability to process complex information quickly and identify strategic patterns, I effectively enhance team dynamics, mentor emerging talent, and drive projects that meet and exceed objectives. I incorporate AI-assisted development into my daily workflow using tools like GitHub Copilot, Cursor, Gemini, and ChatGPT. These tools help me by enhancing prototyping, debugging, refactoring, and architectural exploration while maintaining a strong emphasis on accessibility and human-centered design. Key Skills: Advanced Front-End Development: Deep expertise in React, Next.js, TypeScript, HTML, CSS, and SCSS with a focus on crafting intuitive user interfaces. Leadership & Team Collaboration: Skilled in leading development projects, promoting best practices, and fostering a collaborative team environment. Strategic Problem Solving: Exceptional analytical skills with a knack for tackling complex challenges and delivering practical solutions. ## Work Experience ### Senior Software Engineer @ AllTrails Jan 2022 – Present | Philadelphia, Pennsylvania, United States Since joining AllTrails in 2022, I have led high-impact front-end projects that enhance user engagement, accessibility, and performance. I collaborate closely with design, product, and content teams to build scalable, interactive UI experiences while ensuring best practices in accessibility and performance optimization. Key Contributions: Project Leadership & UI Development: Led the development of a full-page interactive photo tour with a dynamic elevation chart using Swiper.js and Framer Motion. Designed a carousel experience with adaptive layouts, zoom effects, and autoplay while maintaining accessibility. Accessibility & Performance: Advocate for WCAG compliance, ensuring a seamless experience for all users. Engineered keyboard-accessible Recharts components and optimized video autoplay logic to improve performance while reducing unnecessary resource usage. Developer Experience & Tooling: Built server-side conditional rendering strategies, optimizing page load times. Improved CI/CD processes, enhancing front-end maintainability and developer workflows. Cross-Team Collaboration & Knowledge Sharing: Regularly conduct company-wide product demos, ensuring transparency and alignment across teams. I am committed to delivering high-quality, accessible, and performant front-end experiences while improving developer workflows and architectural scalability. I utilize AI/ML tools (GitHub Copilot, Cursor, Gemini, ChatGPT) to accelerate prototyping, improve code quality, and streamline collaboration across engineering and design teams. ### Senior Software Engineer @ Sift Jan 2021 – Jan 2022 | Philadelphia, Pennsylvania, United States Software Engineer working on a Node / React / React Native application that serves 30,000+ daily users. I work primarily on the front end, doing everything from building out a more robust testing suite, to updating core styles to reflect our new design system, to improving the accessibility of our sites, to creating and updating our data analytics events for optimized data analytics. We work in Typescript and use Material UI. Sift makes tools to improve the employee experience for folks across HR, IT, and the everyday employee at a medium to large company. ### Senior Software Developer @ AboveBoard Jan 2020 – Jan 2021 | Philadelphia, Pennsylvania, United States Software developer on a team of 2 building a React / Ruby on Rails app. Continuing a React component library build out from a design system. Establishing our manual QA processes and procedures. Writing and maintaining our Jest tests using React Testing Library. Using React Hooks and Redux Toolkit for state management, and interacting with our Rails APIs. Creating transactional emails using Postmark and the Postmark gem. Integration with Intercom, Heap, and Google Tag Manager. ### Software Developer @ Thrive TRM Jan 2019 – Jan 2020 | Haddonfield, NJ Software Developer working in React and Redux. Implementing Thrive's new design by creating React components using React Hooks and BEM for managing styles. Working from InVision and Sketch design files to create an accessible and beautiful front end for our global users. Creating living documentation with Styleguidist. Building component and app-level test suites with Jest and React Testing Library, improving our code coverage immensely. Working with Redux Toolkit to implement slices of state, rewriting legacy code that was written with Recompose. Learning Ruby and Ruby on Rails. ### Software Developer @ tuzag, inc. Jan 2018 – Jan 2019 | Syracuse, New York Area Software development in React and React Native, with a Node.js and SQL backend. Graphic and UI/UX Design for mobile and web apps, then subsequent build-out in React and React Native. Creation of logo, branding and identity graphics and reusable React components and stylesheets. Creation of marketing websites in Gatsby (React) with chat integration. Creation of investor pitch slide decks. ### Software Developer @ Contract Software Developer Jan 2016 – Jan 2019 | Syracuse, New York Area Worked with various clients, mostly smaller startups, to design and implement mobile and web apps, as well as marketing websites and email templates. Created or worked from style guides to implement brand awareness across all platforms. Constantly learning new codebases, code management, project management, and deployment procedures. Communicated with various stakeholders and end-users to build products that are beautiful, useable, and performant. -HTML, CSS, JavaScript -React, React Native -Firebase, MongoDB, SQL -GitHub, Asana -Adobe Suite -SketchApp ### Front End Development Intern @ Shomeya, Inc Jan 2016 – Jan 2016 | Greater Philadelphia Area Ruby on Rails, SASS, HTML5, CSS, Bootstrap, Middleman, Git, Sketch. Assisting in static website redesign and build out. Learned code management with GitHub and learned command line interface. ## Education ### Bachelor of Arts - BA in Physics, Fine Art Temple University Jan 2002 – Jan 2010 ## Contact & Social - LinkedIn: https://linkedin.com/in/marni-brewster --- Source: https://flows.cv/marni JSON Resume: https://flows.cv/marni/resume.json Last updated: 2026-03-22