Senior Solution Architect, System Assurance and Architecture (AFC)

About the role

GovTech is seeking a Senior Solution Architect (Infrastructure & Security) to play a key role in modernising Singapore's Automatic Fare Collection (AFC) system, which supports Account-Based and Card-Based Ticketing. Working in the System Architecture and Assurance Division, you will lead end-to-end solution design, architecture governance and technical assessments across payment systems, cloud services and multi-vendor integrations, ensuring reliability and security at a national scale.

Key responsibilities

• Design secure, scalable, high-availability AFC and payment solutions, including EMV, open-loop, account-based and card-based ticketing models in the GCC2.0 AWS environment.
• Design and govern end-to-end integration architectures across distributed, multi-vendor environments, using event-driven patterns, message queues (MQ, MQTT), HTTP/S, WebSockets, REST APIs, webhooks and pub/sub.
• Lead security architecture design to meet GovTech's IM8 and security requirements for payment and commuter data.
• Lead network infrastructure design, including network topology, connectivity and security controls in cloud and hybrid environments.
• Maintain architecture and network diagrams, API and interface specifications, and integration designs.
• Translate business and system requirements into technical specifications and perform technical impact analysis for change requests.
• Run solution walkthroughs, architecture reviews and technical presentations, and work with project teams, vendors and financial institutions.

Required profile

• Degree in Engineering, Computer Science, Information Systems or a related field.
• At least 5 years of experience in solution architecture, systems analysis/design or complex enterprise IT infrastructure.
• Working knowledge of network protocols (TCP/IP, HTTP/S, FTPS, SFTP) and the OSI model.
• Experience designing solutions with APIs, webhooks, WebSockets, message queues, MQTT and pub/sub.
• Familiarity with JSON and binary data formats, and with IP addressing, CIDR, subnets, firewalls, routers, MPLS and availability zones.

Required skills

• Bonus: AWS certifications (Associate/Professional) strongly preferred.
• Bonus: experience with AFC systems, open-loop payment architecture or financial-grade transaction systems.
• Bonus: security architecture, tokenisation, encryption, PCI DSS and IM8 compliance.
• Bonus: DevSecOps, CI/CD, containerisation (ECS, EKS), serverless and data streaming.
• Bonus: familiarity with Singapore's Government Commercial Cloud on AWS.