Senior Software Engineer, Web SDK / Frontend Development
Appier is seeking a Senior Software Engineer to lead the development and evolution of its Web SDK, contributing to frontend web UI development for enterprise-facing applications. This role combines deep JavaScript engineering with frontend application development, directly impacting how Appier’s AI capabilities are delivered and experienced at scale. The engineer will collaborate closely with backend engineers, product managers, data teams, and UI/UX designers to deliver robust technical solutions powering Appier’s AI-driven products.
Key responsibilities include leading the long-term evolution of Appier’s Web SDK architecture to enhance scalability, modularity, and maintainability. The engineer will design and refine a robust, extensible SDK foundation supporting multiple products and integration scenarios. Continuous improvement of runtime performance, bundle efficiency, browser compatibility, and overall stability in diverse client environments is essential. Additionally, the role involves contributing to frontend application architecture for enterprise-facing web products, ensuring performance, consistency, and maintainability across shared components.
The ideal candidate has over 5 years of experience in frontend or JavaScript engineering, with strong proficiency in JavaScript (ES6+) and TypeScript. A deep understanding of browser internals, DOM, HTTP, web standards, and client-side performance optimization is required. Experience in designing or maintaining JavaScript SDKs, libraries, or shared frontend modules is essential. In-depth knowledge of front-end frameworks and technologies, such as React.js or Vue.js, and their ecosystems is also necessary. Solid knowledge of version control (Git) and CI/CD workflows, along with experience in writing unit, integration, and end-to-end tests, is expected. Strong problem-solving skills, an ownership mindset, and the ability to collaborate effectively in cross-functional teams are crucial.
Preferred qualifications include familiarity with modern build tools and bundlers like Babel, Webpack, Vite, Rspack, or esbuild. Experience in Node.js, Python, GraphQL, and integrating with various backend services and databases such as MySQL or MongoDB is advantageous. Proficiency with testing frameworks like Jest, Vitest, or Playwright, and experience with cross-browser compatibility and performance tuning in complex browser environments are beneficial. Familiarity with web security practices, such as CSP and XSS mitigation, and experience with micro-frontend architecture are also desirable.
Appier offers a dynamic work environment where engineers have meaningful ownership while collaborating with experienced cross-functional teams. The role provides opportunities to work on real-world browser challenges, performance optimization, and SDK architecture, directly powering AI-driven experiences embedded in enterprise websites at scale.