Senior Software Engineer (Kotlin, ReactJS) - Public Sector Digital Service

About the role

Activate Interactive, a technology consultancy in Singapore, is hiring a Senior Software Engineer (Kotlin, ReactJS) for its Co-Development Business Unit. You will work on a Singapore government agency project, modernising a public sector digital service by migrating a legacy tech stack to a modern, cloud-native, containerised platform on AWS. This is a fixed-term contract of 1 year.

Key responsibilities

• Migrate legacy applications to a cloud-native, containerised stack and build products end to end, from frontend to backend, infrastructure, security integration and production support.
• Build responsive, accessible web frontends with ReactJS, TypeScript and Next.js.
• Develop backend services and APIs in Golang and/or Kotlin, including long-running business processes with a workflow engine such as Temporal.
• Set up and maintain secure AWS infrastructure using Infrastructure as Code (e.g. Terraform).
• Implement security controls and monitoring, including authentication and identity integration with Singpass, Corppass, OIDC and SAML.
• Build and maintain CI/CD pipelines in GitLab and deploy workloads to Kubernetes (EKS); instrument applications for observability with tools such as Dynatrace or Datadog.
• Support production deployments, troubleshoot issues and take part in incident resolution.
• Define the technical architecture and target state, lead delivery across workstreams, coordinate with product owners, DevSecOps and agency stakeholders, and mentor team members.
• Plan legacy-to-modern migration approaches, including sequencing, risk management and cutover, and write clean, tested, documented code with code reviews.

Required profile

• Experience migrating or modernising legacy systems is strongly preferred.
• Experience delivering Singapore Government or public sector projects is an advantage.
• Senior consultant level: proven leadership, stakeholder management and ability to drive decisions.

Required skills

• Frontend: ReactJS, TypeScript, Next.js
• Backend: Golang and/or Kotlin
• DevOps: CI/CD, Docker, Kubernetes
• Cloud: AWS architecture and services (S3, EKS/ECS, EC2, Lambda, RDS, Load Balancers, API Gateway)
• Infrastructure as Code: Terraform (or equivalent)
• Observability: hands-on experience with at least one tool such as Dynatrace or Datadog
• Workflow and rules engines (e.g. Temporal, Gorules, Open Policy Agent)
• Identity and security tooling: Singpass, Corppass, ADFS, WOG AD, CAM, Trend Micro FAM, RBAC/ABAC

What we offer

• Market-competitive salary and variable performance bonus.
• Medical coverage, life and health insurance, and flexible benefits or allowance.
• Wellness support, learning programmes, certification support and a staff development budget.
• Structured career pathways on technical, domain expert or leadership tracks.
• Flexible work arrangements (flexi-place, flexi-time, flexi-load).