Senior Business Analyst (fixed-term contract)

Who We Are Located in the heart of Bangkok’s Phrom Phong District, Sertis is ASEAN's leading Data and AI engineering and solutions company. Since 2014, our advanced solutions and products have powered over 400 enterprise Data and AI deployments at the region’s leading companies and conglomerates. We are also a member firm of Andersen Consulting, a global consulting practice integrating business strategy, digital transformation, and AI-driven technology solutions with Andersen Global’s world-class expertise. What We Do Sertis provides both productized and bespoke AI and Data solutions for our Customers, optimizing and commercializing their data in ways that activate real business results. Our 140+ team have developed product offerings and IP ranging from advanced Computer Vision applications accredited Global Top 20 by NIST, to automated insights monetization for Retailers, eKYC for financial institutions, AI-driven agricultural safety assurance, precision steel cutting, trading algorithms for hedge funds, and enterprise knowledge management systems based on AI. Our Aspiration We are data and AI pioneers, dedicated to enhancing the economic and social lives of our customers via technology. We are not just living in history, we are making history everyday. In becoming one of the world’s leading Data and AI companies, we always double-down on remaining a place where a diverse mix of talent wants to come, do their best work, and stay. We pride ourselves on bringing the best talent worldwide into a culture that encourages learning, growth opportunities, innovative contributions, and a sense of ownership. As part of Andersen Consulting, we are committed to delivering best-in-class Data and AI solutions—aligned with a global platform known for innovation, integration, and impact—while continuing to set benchmarks in the region and beyond. For more information, please visit: sertiscorp.com About the job We are looking for a Senior Business Analyst with an account-facing mindset to serve as a key bridge between clients and internal teams. This role goes beyond traditional BA work, you will own client relationships, proactively manage accounts, and drive end-to-end delivery of features and solutions from requirements through to go-live. If you thrive in both technical conversations and client-facing environments, this role is for you. This role is based at our client's site in the Nonthaburi area, requiring 3-4 days WIO. In this role, you will get to: Account Management Serve as the primary point of contact for assigned client accounts, building and maintaining strong, long-term relationships Proactively engage clients to understand evolving business needs, surface opportunities, and manage expectations throughout the project and product lifecycle Lead regular client check-ins, status updates, and review meetings to ensure alignment and satisfaction Identify and escalate risks, issues, or change requests early, working with internal stakeholders to resolve them efficiently Support account growth by understanding client goals and connecting them with the right solutions Business Analysis Lead requirement-gathering sessions with clients when new features or system enhancements are requested, ensuring needs are clearly captured, scoped, and prioritized Translate complex business requirements into detailed functional specifications, process flows, use cases, and solution proposals for the development team Act as the voice of the client internally, ensuring delivered solutions genuinely address business needs Participate in and contribute to projects following SDLC or Agile methodologies Plan, coordinate, and lead System Integration Testing (SIT) and User Acceptance Testing (UAT) with clients and internal QA teams Define test scenarios and acceptance criteria in collaboration with clients and technical teams Track, document, and manage defects and issues through to resolution during testing phases Ensure smooth project go-live by coordinati…