Senior Software Engineer (App Integration)

We are building a new marketplace platform to modernize how we process orders across multiple sale channels. The platform replaces a legacy monolithic system with purpose-built services for channel integration and order fulfillment. As the Senior Software Engineeer , you will own the technical direction and delivery of this platform from day one. You will lead a dedicated build team through the initial delivery, then evolve into leading two permanent squads as the team converges with the existing marketplace team. This is a dual-track role: you will drive a greenfield platform build while maintaining oversight of a legacy system during a parallel migration period. You will also pioneer AI-native development practices, using AI pair programming as a core part of the team’s workflow. What You'll Do Technical Leadership Design and review event-driven distributed systems across platform services Define API contracts, messaging topology (SNS/SQS), and database schemas (PostgreSQL) Establish architecture patterns: adapter-based channel integration, state machine-driven fulfillment workflows, DLQ handling Evaluate and review AI-generated code critically — ensuring quality, security, and maintainability Own technical decision-making for the platform, balancing speed with long-term maintainability Delivery & Process Lead end-to-end platform delivery from design through production go-live Run tight sprint cadences with clear goals and retrospectives Establish code review standards, CI/CD pipelines, and deployment practices Set up on-call rotations, incident response processes, and runbook documentation Coordinate knowledge transfer from the existing team during the build phase People & Growth Build and lead the new platform team from onboarding through production delivery After go-live, lead the convergence of the new and existing teams into two purpose-built squads Mentor existing .NET developers transitioning to the TypeScript stack Span both squads long-term, providing architectural oversight across the domain Must Have 6+ years of backend engineering experience, with 2+ years in a tech lead or senior architect role Strong proficiency in TypeScript and Node.js Deep experience with event-driven architectures: message queues (SQS, SNS, Kafka), async workflows, idempotency patterns Production experience with AWS services: EKS/Kubernetes, Aurora/RDS (PostgreSQL), ElastiCache (Redis), SQS/SNS Experience designing and operating distributed systems with proper observability (structured logging, distributed tracing, dashboards) Proven ability to run agile delivery: sprint planning, backlog management, retrospectives Strong code review culture — can review PRs for correctness, security, and design quality Nice to Have Familiarity with .NET 6 / .NET Framework (for legacy oversight during migration) Experience with AI pair programming tools (Copilot, Claude, Cursor) and AI-native development workflows Experience migrating systems from monolith to microservices Contract testing experience (Pact or similar) Experience integrating with third-party marketplace APIs (e.g., Shopee, Lazada, Grab, or similar) Tech Stack Backend - TypeScript, Node.js Database - PostgreSQL (Aurora), Redis (ElastiCache) Messaging - Amazon SQS, SNS, with DLQ patterns Infrastructure - AWS EKS (Kubernetes), Terraform, GitHub Actions CI/CD Observability - Datadog (tracing, logging, dashboards, alerting) Frontend (Packing UI) - React, Vite, TypeScript Legacy (oversight) - .NET 6, .NET Framework 4.7.2, SQL Server, MongoDB