Senior Full Stack Developer - React, C# .NET, Typescript

Build smart, scalable solutions from end to end. We’re looking for a Senior Full Stack Developer who enjoys solving complex problems, shaping quality software, and working across modern frontend and backend technologies. If you bring strong engineering judgement, clean coding standards, and the confidence to contribute to architecture and delivery, this role is built for you.

Work Setup: Fully remote with onsite schedules upon client request

Role Overview

As a Senior Full Stack Developer, you’ll help design, build, and maintain high-quality web applications using React, TypeScript, and C#/.NET. You’ll work closely with product, design, and engineering teams to deliver reliable, accessible, and scalable solutions while lifting code quality, technical direction, and engineering best practices across the team.

Key Responsibilities

• Build Across the Stack: Design, develop, and maintain full-stack applications using React, TypeScript, and C#/.NET.

• Create Better Experiences: Build responsive, accessible, and user-friendly interfaces that make complex workflows feel simple.

• Strengthen the Backend: Develop APIs, backend services, and database solutions that are reliable, secure, and easy to maintain.

• Partner Across Teams: Collaborate with product, design, and engineering stakeholders to deliver new features and thoughtful improvements.

• Shape Technical Direction: Contribute to design discussions, architecture decisions, and practical engineering standards.

• Keep Code Quality High: Write clean, maintainable, well-tested code that supports long-term product growth.

• Lift the Team: Review code, share ideas, and support continuous improvement across engineering practices.

• Solve Problems Quickly: Troubleshoot, debug, and resolve issues across frontend and backend systems.

• Design for Scale: Improve application performance, scalability, accessibility, security, and reliability.

• Stay Curious: Keep up with emerging technologies and bring practical ideas into the development process.

Skills & Experience

Required

• 5+ years’ experience shipping production software as a Full Stack Engineer, with strong frontend and backend capability.

• Deep experience with React and TypeScript, including strict mode, generics, discriminated unions, hooks, and modern development patterns.

• Strong C#/.NET experience, including minimal APIs, async/await, Entity Framework Core or similar ORM, and recent .NET versions.

• Strong relational database experience, ideally PostgreSQL, including schema design, complex queries, and migrations.

• Experience designing and maintaining REST APIs, service contracts, and integration best practices.

• Solid understanding of accessibility standards, including WCAG 2.1/2.2 AA, ARIA, keyboard navigation, and screen reader testing.

• Strong testing discipline across unit, integration, and end-to-end testing frameworks.

• Based in Australia with full working rights.

Nice to Have

• Experience building or contributing to design systems, including tokens, primitives, theming, and versioning.

• Experience developing canvas-based, drag-and-drop, or visual editor interfaces using tools such as React Flow, xyflow, or dnd-kit.

• Experience building real-time applications using SignalR, WebSockets, or similar technologies.

• Exposure to workflow or rules engines such as Elsa or Flowable.

• Experience working with event-driven architectures using RabbitMQ, Kafka, or similar technologies.

• Experience working within Kubernetes and Helm environments.

• Comfort using AI-assisted development tools such as Claude Code, Cursor, or GitHub Copilot beyond basic autocomplete.

What’s in It for You

• Flexibility that Fits: Hybrid options across Makati and Pampanga, on day shifts aligned with our Australian clients.

• Workspaces that Work: Modern offices built for focus, collaboration, and real productivity.

• Coffee and Good Company: Barista coffee on demand and a café bar to unwind after work.

• Meals on Us: Complimentary meals once a week on your on-site day.

• Covered from Day One: Health coverage with free dependent coverage, so you're looked after from the start.

• Compensation You Can See: Transparent salary packages with direct client involvement.

• Room to Grow: Ongoing training and real opportunities to step into bigger roles.

• An Award-Winning Home: Join a team ranked 8th Best Workplace in the Philippines and recognised among Fortune Best Workplaces in Southeast Asia.

• People Who Have Your Back: Work alongside reliable, easy-going people who care about doing great work.

• A Global Stage: Work directly with international clients and see how teams scale worldwide.

About Us
At hammerjack, we connect skilled professionals in the Philippines with growing businesses across Australia and beyond—building teams that work as true extensions of our clients. We're proud to be named among the Fortune 100 Best Workplaces in Southeast Asia and ranked the 8th Best Workplace in the Philippines.

Our Impact
Our people aren't outsourced—they're embedded. With aligned tools, shared goals, and real accountability, they deliver at the same standard and pace as onshore teams while building long-term careers they're proud of, across accounting, tech, admin, and marketing.