About Appier 

Appier is a software-as-a-service (SaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information.

About the role

Frontend engineers at Appier focus on handcrafting sophisticated web UI using cutting-edge front-end development technologies / tools. We work closely with UI/UX designers and backend engineers and deliver high-quality, fluent and elegant web applications to our enterprise customers, or to aid daily operations within Appier.

 [The seniority/title is determined by job-related skills, experience, and evaluation after the interview.]

Responsibilities

• Design & develop front-end architecture & interactive user interfaces
• Work closely with backend engineers to integrate services, and contribute to building lightweight RESTful APIs when necessary to support frontend functionality
• Ensures the flexibility of front-end architecture and the high performance of responsiveness
• Build reusable code and UI design systems for cross-product consistency and scalability
• Write unit, integration, and end-to-end tests to ensure code quality
• Perform code reviews to ensure existing code stay high-quality, fast, and flexible
• Handle and resolve issues escalated from the production operational environment
• Participate in idea brainstorming and contribute ideas to technology, algorithms and products

About you

[Minimum qualifications]

• 3+ years of experience in software development
• Good knowledge of HTTP, CSS, modern JavaScript (ES6+ / ECMAScript 2015+), TypeScript, HTML, DOM, and web standards
• Respect coding convention, language standard syntax, documentation
• In-depth knowledge of front-end frameworks and technologies (e.g., React.js, Vue.js) and their ecosystems.
• Proactive, good interpersonal and problem-solving skill
• Self-motivated, proactive, and a strong team player
• Solid understanding of version control (Git) and CI/CD workflows
• Experience leveraging AI-assisted development tools (e.g., GitHub Copilot, Cursor, Windsurf) to accelerate coding, debugging, and refactoring. Familiarity with these tools is expected as part of our team’s daily development workflow.
• Passion for clean code, scalability, and performance, curious about new technologies and enthusiastic about developer experience
  
  

[Preferred qualifications]

• Familiarity with modern build tools and bundlers (e.g., Babel, Webpack, Vite, Rspack, esbuild, etc.)
• Experience in CSS Pre/Post-processors (PostCSS, SASS or LESS) or modern CSS solutions (e.g., CSS Modules, Tailwind CSS, Styled Components).
• Experience in Node.js, Python, GraphQL, and integrating with various backend services and databases (e.g., MySQL, MongoDB)
• Experience with testing frameworks such as Jest, React Testing Library, Vitest, or Playwright
• Experience building or integrating SDKs or capable of developing across multiple browsers, platforms
• Experience in web performance optimization
• Familiarity with micro-frontend architecture
• Experience with data visualization

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About Appier 

Appier is a software-as-a-service (SaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information.

About the role

Frontend engineers at Appier focus on handcrafting sophisticated web UIs and ad content using cutting-edge front-end development technologies and tools. We collaborate closely with designers and backend engineers to deliver high-quality, smooth, and elegant web applications for the advertising domain as well as support daily operations within Appier.

 [The seniority/title is determined by job-related skills, experience, and evaluation after the interview.]

 Responsibilities

• Design and develop reusable advertising UI components (e.g., banners, video ads) and supporting systems using modern JavaScript frameworks and AI-powered tools.
• Build and maintain a modular JavaScript library or SDK to ensure scalable, consistent, and easily integrated ad rendering and tracking.
• Optimize ad content performance through efficient loading strategies and responsive design.
• Develop integrations with external SSP platforms, ensuring compliance with technical standards.
• Implement and manage analytics tools to monitor user interaction and ad effectiveness, delivering actionable insights.
• Participate in brainstorming sessions, contributing innovative technical solutions across UI/UX, algorithms, and product development.
• Utilize AI-powered development tools (e.g., GitHub Copilot, Tabnine, Cursor) to enhance coding efficiency and maintain code quality.

About you

[Minimum qualifications]

• Solid understanding of HTML, CSS, JavaScript, TypeScript, DOM, HTTP and web standards.
• Knowledge of modern front-end frameworks like React, Vue, Svelte.
• Experienced in integrating with REST APIs and GraphQL
• Experienced with bundler: Vite, Webpack, esbuild, and Rollup.
• Familiarity with Git for version control.
• Experience ensuring cross-browser compatibility.
• Practice coding conventions, syntax standards, and thorough documentation.
• Shows initiative and strong interpersonal skills in problem-solving.
• Ability to work effectively both independently and as part of a team.

[Preferred qualifications]

• Explores and shares insights on AI tools like GitHub Copilot, Tabnine, Cursor, and AI-driven testing to enhance front-end development and code quality.
• Experienced with meta frameworks like: Next.js, Nuxt.js, SvelteKit.
• Experienced with CSS-in-JS, PostCSS, SASS, and Tailwind CSS.
• Skilled in Jest, React Testing Library, Cypress, and Playwright for testing.
• Experienced in web performance optimization using Core Web Vitals, Lighthouse, WebPageTest, and Chrome DevTools.
• Experienced in debugging on any web environments like webview or browser.
• Experienced in server-side JavaScript runtime: Node.js, bun, deno.
• Experienced with relational databases or NoSQL databases.
• Familiar with CI/CD tools (GitHub Actions, Jenkins, Bitbucket) and Docker.

#LI-AK1

About Appier 

Appier is a software-as-a-service (SaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information.

About the Role

We are seeking a Senior Software Engineer who will primarily lead the development and evolution of the Appier Web SDK, while also contributing to frontend web UI development for enterprise-facing web applications.

This position combines deep JavaScript engineering with frontend application development. You will work on improving the reliability, performance, and extensibility of Appier Web SDK, while also contributing to frontend architecture for enterprise-facing SaaS applications. Your work will directly impact how Appier’s AI capabilities are delivered and experienced at scale.

You will collaborate closely with backend engineers, product managers, data teams, and UI/UX designers to deliver robust technical solutions that power Appier’s AI-driven products.

 [The seniority/title is determined by job-related skills, experience, and evaluation after the interview.]

Why This Role Is Exciting

• You will work on real-world browser challenges, performance optimization, and SDK architecture — not just UI feature implementation
• You will have meaningful ownership while collaborating with experienced cross-functional teams
• Your work will directly power AI-driven experiences embedded in enterprise websites at scale

Responsibilities

• Lead the long-term evolution of Appier’s Web SDK architecture, strengthening its scalability, modularity, and maintainability to support future product growth
• Design and refine a robust, extensible SDK foundation that can support multiple products, integration scenarios, and enterprise-scale deployments
• Continuously improve runtime performance, bundle efficiency, browser compatibility, and overall stability in diverse client environments
• Contribute to frontend application architecture for enterprise-facing web products, ensuring performance, consistency, and maintainability across shared components
• Identify technical debt and architectural risks early, and proactively implement sustainable improvements rather than short-term fixes
• Safeguard quality through thoughtful testing strategies and thorough code reviews, helping maintain a strong engineering culture
• Support production stability by investigating and resolving client-side issues when needed
• Participate in product and technical roadmap discussions to ensure the SDK platform evolves in alignment with business and platform strategy

About You

[Minimum qualifications]

• 5+ years of experience in frontend or JavaScript engineering
• Strong proficiency in JavaScript (ES6+) and TypeScript
• Deep understanding of browser internals, DOM, HTTP, web standards, and client-side performance optimization
• Experience designing or maintaining JavaScript SDKs, libraries, or shared frontend modules
• In-depth knowledge of front-end frameworks and technologies (e.g., React.js, Vue.js) and their ecosystems.
• Solid knowledge of version control (Git) and CI/CD workflows
• Experience writing unit, integration, and end-to-end tests
• Strong problem-solving skills and ownership mindset
• Self-motivated, proactive, and able to collaborate effectively in cross-functional teams
• Experience leveraging AI-assisted development tools (e.g., GitHub Copilot, Cursor, Windsurf) to accelerate coding, debugging, and refactoring. Familiarity with these tools is expected as part of our team’s daily development workflow.
• Passion for clean code, scalability, and performance, curious about new technologies and enthusiastic about developer experience
  
  

[Preferred qualifications]

• Familiarity with modern build tools and bundlers (e.g., Babel, Webpack, Vite, Rspack, esbuild, etc.)
• Experience in Node.js, Python, GraphQL, and integrating with various backend services and databases (e.g., MySQL, MongoDB)
• Experience with testing frameworks such as Jest, Vitest, Playwright, or similar
• Experience with cross-browser compatibility and performance tuning in complex browser environments
• Familiarity with web security practices (CSP, XSS mitigation, etc.)
• Experience with micro-frontend architecture

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