Full Stack Software Engineer - Agentic AI

Join NinjaTech AI as a Software Development Engineer: you will learn and use the latest tech to innovate, build and scale long-running AI agents, intelligent Apps and automations (B2B and B2C), powered by SuperNinja - our advanced agentic AI platform with full OS capabilities. About the Company: NinjaTech AI is a generative AI startup with headquarters in Silicon Valley and a subsidiary in Sydney. NinjaTech AI is backed by Alexa Fund and Samsung Ventures and we are on track to raise Series A funding in 2026. You will contribute to building an agentic AI platform featuring autonomous long-running AI agents, each on dedicated computers with browser, code editor, terminal, and tool integrations. Our AI Agents handle tasks like browsing, coding, workflow automation, data analysis, reporting, building AI-native apps, competitive intelligence, and content production. About the Role: The Software Engineer is a full-time position, based at our Sydney office (5 days on-site; fantastic office space, free daily meals). Our team works in a fast-paced and collaborative environment. We get a lot done when we ideate together and iterate quickly. The Software Engineer will design, develop, integrate and deploy various AI technologies within NinjaTech’s Agentic AI product. You will report to the VP of Engineering (ex-AWS, onsite in Sydney) and will collaborate daily with the Chief Science and Technology Officer/Co-founder (ex-AWS, Sydney) and Founder/CEO (ex-Google, HQ), as well as our strong team of Software Engineers and Applied Scientists, PM, UX, and QA. What you will do: As a key member of our engineering team, the Software Developer will be responsible for translating our vision and customer needs into functional and appealing interactive applications, ensuring a great user experience. Build features (end-to-end) for our web app (super.myninja.ai)Bring expertise in performance and optimization to improve our applications for smooth and fast user experience. Develop and maintain documentation for the platform, including API documentation. Write clean, efficient, and well-documented code in React, Next.js, Python and ensure code quality through automated testing and continuous integration and deployment. Participate in code reviews and provide constructive feedback to other members of the team. Troubleshoot and debug issues that arise in the platform, and implement solutions to prevent recurrence. Collaborate with product management to define and prioritize product requirements, ensuring technical feasibility and alignment with company goals and user requests. Leverage RESTful APIs and web sockets for fast communication with our backend systems. Unit-test code for robustness, including edge cases, usability, and general reliability. Continuously discover, evaluate, and implement new technologies to maximize development efficiency. Required Experience: 1+ year(s) of experience in software development, with a focus on building scalable and reliable web applications. Generalist mindset: you're comfortable working across frontend, backend, and infra. You see every layer as an exciting opportunity to make an impact. Professional experience in at least one of: Python, React, Node.js, or Next.js and curiosity to learn the restFamiliarity with cloud platforms (AWS strongly preferred) and databases (Supabase, PostgreSQL, DynamoDB, Firebase, etc.)Systematic thinker: you design before you code and you care about how things are built, not just that they workOwnership mentality: you take problems from start to finish without needing to be told what's nextStrong problem-solving skills and ability to work in a team environment. Bachelor's degree in Computer Science or relevant field preferred. Nice to Have: Startup experience: you've shipped in fast-moving, ambiguous environmentsEnd-to-end projects you've built yourself (side projects, open source, hackathons)Experience with TypeScript, WebSockets, CI/CD pipelines, or service-oriented architecturesInterest in AI/ML and how large language models work Benefits: NinjaTech AI offers excellent benefits: Annual Health insurance subsidySuperannuationPaid Time Off (Vacation, Sick & Holidays)Paid meals and snacksStock Option Plan Compensation Range: A$160K - A$190K