Senior Frontend Engineer (SWE III)

What We're Looking For We are looking for an experienced Senior Frontend Engineer (SWE III) to help build Zaapi's AI-first Helpdesk and AI Agent across web and mobile. You will take full ownership of major features end to end, and work closely with Product, Design, and the rest of Engineering to ship them. Our product has two halves that need to work as one. The Helpdesk is where merchants run their day-to-day customer conversations across every channel their buyers use - WhatsApp, LINE, Facebook, Instagram, Shopee, Lazada, TikTok Shop and Shopify. The AI Agent is where those conversations get resolved automatically: retrieving the right knowledge, following the merchant's own procedures, and taking real actions inside marketplaces and storefronts on the merchant's behalf. That combination makes this a demanding frontend problem. Merchants live in the product all day, on desktop and on their phones, so the web app (React) and the mobile app (React Native) both have to stay fast and reliable under real conversation volume. And because the AI Agent is the core of the product, you should have built agentic applications yourself - not just used AI tools - and have a view on how these systems behave, and misbehave, in front of a user. This is a senior, hands-on role. You will define the frontend architecture and standards the team builds on, make the call on how features are built, and own them through deployment, monitoring, and iteration. If you want to build AI products that do real work for real businesses, and want to grow with a fast-scaling AI startup, this role is for you. Responsibilities Feature Ownership: Take full ownership of major features across the web and mobile applications, from planning and implementation through to deployment, monitoring, and iteration.Frontend Architecture: Define and evolve Zaapi's frontend architecture, patterns, and technical standards, and bring the rest of the team along with them.Performance & Scale: Build for complex, high-volume use, where performance optimisation and scalability are part of the design rather than an afterthought.AI-Powered Engineering: Evaluate and share AI-powered tools and techniques that improve engineering productivity, development speed, and code quality.Production Quality: Triage complex bugs and production issues, working closely with the Commercial team to communicate impact, timelines, and possible workarounds for customers.Cross-Functional Collaboration: Work with Product, Design, and Engineering stakeholders to deliver high-quality solutions aligned with customer and business needs. Location Bangkok (Hybrid - in office 3 days a week) or remoteOffice near Thonglor BTS station Minimum Qualifications 4+ years as a frontend engineer using React, and comfortable working full-stack when necessaryExperience with complex web applications where performance optimisation and scalability considerations are essentialYou've built agentic applications, not just worked with AI toolsExperience with most of the following: TypeScript, React, React Native, Vercel, EASExcellent written and verbal communication skills in English Preferred Qualifications Deep experience with React Native, building modern user experiences and optimising mobile app performanceFamiliarity with backend technologies such as NestJS, MongoDB, AWSPrevious experience in an early-stage or fast-scaling startup Benefits Health insuranceFlexible Benefit: USD 600 per yearHybrid working14 days of annual leaveInternational working environment About Us Zaapi (https://www.zaapi.com) is the AI Customer Experience (CX) platform designed for the modern era of commerce. Backed by Global Founders Capital, Flash Ventures, Partech, Flourish Ventures, Tekton Ventures, 1982 Ventures, Iterative VC, Kaya Founders and other leading global investors.