• Translate high-level business problems into functional AI solutions by creating and executing end-to-end solutions • Design, build, and maintain backend services and APIs that deploy and integrate AI-powered features using existing foundational models (e.g., OpenAI, Claude, Hugging Face, etc.) • Implement scalable, reliable, and maintainable backend architecture supporting AI workflows, automation, and data processing pipelines • Integrate AI services into complex technology stacks, ensuring interoperability with microservices, AWS platform, and data systems (Snowflake) • Enable rapid test-and-learn cycles by building experimentation frameworks that support iterative deployment of AI-driven functionalities • Collaborate closely with cross-functional teams including product managers, data scientists, and frontend engineers to translate business needs into technical implementations • Stay abreast of the AI ecosystem, frameworks, and tools to guide implementation decisions and technical evaluations for adopting new AI capabilities • Document backend system designs, APIs, workflows, and integration patterns clearly for team knowledge sharing and operational continuity.

Stack Builders is an international software development consultancy dedicated to delivering high-quality, modern software solutions. Our team thrives on curiosity, collaboration, and continuous learning, helping clients bring innovative ideas to life using best-in-class technologies and practices. We are looking for a Senior Fullstack TypeScript Developer with a strong backend -orientation to join our Documentation as Code (DaC) platform team. This role is ideal for someone who excels at building scalable backend systems using TypeScript, while also being comfortable contributing to a modern React-based frontend.

• Design and build large-scale backend systems for money movement with strict correctness requirements • Architect clean, extensible abstractions for complex payments infrastructure — making it easier for other teams to interface with financial rails • Build systems that handle both traditional banking and emerging crypto payment rails • Interface with diverse third-party banking and payments partners to accelerate feature delivery • Own problems end to end — from technical architecture to production reliability to partner integrations • Bring deep attention to detail to financial systems where doing things right matters more than moving fast

Company Overview WEX is an innovative global commerce platform and payments technology company looking to forge the way in a rapidly changing environment, to simplify the business of doing business for customers. We are journeying to build a consistent world-class user experience across our products and services and leverage customer-focused innovations across all our strategic initiatives, including big data, AI, and Risk. Position Summary We are looking for a highly motivated and highly potential Staff Engineer to join our Risk Engineering team to make big business impacts and grow your career. This is a really exciting time to be in risk technology at WEX. We are hiring for a cross-functional initiative with the goal of creating a modern, cloud-based technology ecosystem to allow WEX to be more nimble, faster to market, and open to emerging business opportunities, while keeping regulations, policy, and risk mitigation top of mind. We are in the process of building a powerful platform for risk operation & management, credit underwriting & management, finance risk operation & management, on top of our Data Platform and AI Platform, leveraging open source technologies as well as vendor platforms and tools. The vision of this integrated risk platform is to enable streamlining how WEX interacts with customers - from creating accounts, maintaining and expanding relationships, and monitoring for good health and risk through a number of vectors. With strong risk control and management, this platform will allow Wex to more effectively grow our business and customer base in a much faster and safer way together with improved customer experience. We develop and leverage advanced technologies from the industry to ensure our efficiency and effectiveness, including modern big data technologies and AI technologies. We use agile development with the combined engineering approach and the product operating model. We have challenging problems with huge business impact potentials for you to lead, work on and grow. We also have a strong team with highly talented and skillful engineers and leaders to support, guide, coach you. If you dream to be a strong engineer who can solve tough problems, lead, generate big impacts, and grow fast, this is a great opportunity for you! Responsibilities: - Collaborate with partners/stakeholders to learn about our customers’ business and key challenges. - Design, test, code, and instrument new data products/systems/platforms/pipelines at large complexity level with simple and high quality solutions. - Effectively measure, inspect, and drive decisions using data. - Effectively develop and maintain CI/CD automation using tools such as GitHub Actions. - Effectively implement Infrastructure as Code (IaC) using tools like Terraform, including provisioning and managing cloud-based data infrastructure. - Effectively perform software development with TDD and BDD, Microservice and event oriented Architectures with high efficiency, reliability, quality, and scalability. - Support live Risk platforms/systems, promote proactive monitoring including high data quality, rapid incident response, and continuous improvement. - Effectively analyze data, existing systems and processes independently to effectively identify bottlenecks and opportunities for improvements. - Mentor your peers, foster continuous learning of new technology within your team and organization. - Attract high talents from industry to your team; help in interviews and provide quality and timely feedback. - Role model at our team’s process and best practices, and apply them to given tasks with help from peers and your manager. Proactively understand customer/business problems you try to solve with these tasks, and ensure your design and implementation can actually solve these problems in an effective, reliable, and sustainable way. - Partner with, assist, or lead your peers on completing complex tasks. - Take strong ownership/accountability, be proactive, and lead. - Lead a scrum team in a hands-on way with proper agile development practices, and ensure the high quality and timely development and delivery that solve target problems effectively. - Own large complex components or systems/platforms. - Participate and lead technical discussions. - Very efficiently design and build high quality and performed systems with craftsmanship. - Independently & productively complete work at medium/large complexity level and proactively seek reviews from senior engineers on your work to ensure high quality - Proactively identify and communicate dependencies. - Proactively review work from peers and provide constructive feedback/comments. - Build reliable, secure, high quality, and efficient Risk platform, systems, and tools. - Become a deep subject matter expert in your functional area and best practices. - Assess unique circumstances and apply creative problem-solving techniques to resolve issues or suggest various approaches. - Use data and/or AI technology or tools in solutions you design/develop for more effective business outcomes and better customer experience as well as in your design & development work for high productivity and better solution quality. Influence your peers in this area. - Effectively and efficiently analyze data to deeply understand risk problems and build effective solutions. - Eager and good at learning and exploring new technology and innovative approach to improve effectiveness and productivity. Bring the learnings to the team to lead team’s grow together. - Lead initiatives for your team by using your wide-ranging experience and deep technical knowledge to make decisions on method and approach to solving issues. - Hold yourself and your team accountable for delivering quality results using defined OKRs. - Interact with Senior Managers to discuss plans, results, and advise on complex matters. Required Qualifications: - Bachelor's degree in Computer Science, Software Engineering, or related field. OR demonstrable equivalent deep understanding, experience, and capability. 7+ years of experience in software engineering at a large scale. - Master or PhD degree in Computer Science (or related field) and 5+ years of experience in software engineering. Experience in Risk system/platform development. - A technically deep, innovative, empathetic, and passionate technical leader able to act and deliver to the business needs. - Very strong problem-solving skills, excellent communication and collaboration skills. - Highly self motivated and eager to learn. Always watching out for new technologies and adopting appropriate ones for improving your productivities as well as the quality & effectiveness of your deliverables. E.g. good at leveraging GenAI technology and tools for increasing your work productivity and quality, as well as building innovative products/systems for your customers. Lead the team in this regard. - Rich experience in designing a simple, high quality, performed, and efficient solution for a large complex level problem. - Rich experience and good understanding of CI/CD automation. - Rich experience in combined engineering practice and agile development. - Very rich experience and strong implementation skills using languages like TypeScript, Python, including coding, automated testing, measurement and monitoring with a high productivity/throughput. Experienced in TDD approach. - Experience and with good understanding of data processing techniques, such as data pipeline/platform development, SQL, and DBs are a big plus. - Experienced in cloud technology, such as AWS and Azure. - Extensive experience in the risk area, including architecturing and developing Risk platforms. - Good understanding and experience in Data and ML/AI, as well as applying those to solve risk problems. - An understanding of and experience in payment organizations is a plus. - Good understanding of data warehousing and dimensional modeling, etc. - Passionate about understanding and solving customer/business problems. - GenAI Expertise: Deep understanding of the Generative AI lifecycle, including prompt engineering, Retrieval-Augmented Generation (RAG), and fine-tuning strategies. - Agentic Engineering: Knowledge about GenAI and Agentic Engineering, experience building autonomous agents that can plan, use tools, and self-correct. - Understanding of data governance is a plus. - Strong understanding of algorithm design and performance