Senior Full Stack Engineer (AI-Native B2B Tax Software)

We are looking for a Senior Full Stack Engineer to join a team developing AI-native B2B tax software. This role is ideal for an experienced engineer who enjoys building production applications, owning features from end to end, and helping improve engineering processes through automation and AI-powered workflows. You will initially focus on designing and establishing a reliable Playwright E2E test automation suite. As the foundation is established, you will take on full-stack feature development across the frontend, backend, database, and cloud infrastructure. You will work closely with founders and the engineering team to turn business requirements into scalable, high-quality technical solutions. Key Responsibilities: Develop and maintain production web applications using Next.js, React, Python, and Django. Design, build, and own Playwright E2E automation, including test architecture, regression coverage, and CI/CD integration. Own features throughout their full lifecycle, from solution design and implementation to testing, deployment, and post-release support. Design and optimize PostgreSQL databases, including schema design, migrations, and query performance. Work with AWS infrastructure, including ECS/Fargate, RDS, and S3. Conduct code reviews and contribute to engineering standards and best practices. Identify and improve inefficiencies in development and engineering processes. Make independent technical and architectural decisions, considering scalability, maintainability, and performance. Collaborate with founders and stakeholders to translate business requirements into technical solutions. Use AI tools for coding, debugging, planning, testing, and code review. Develop AI-powered workflows, prompts, automations, or integrations to improve engineering productivity. Contribute to a collaborative, cross-functional team where engineering, QA, DevOps, and product responsibilities may overlap. Requirements: At least 6 years of experience building and shipping production web applications. Strong hands-on experience with React and Next.js in production environments. Strong backend development experience using Python and Django. Experience with PostgreSQL, including database design, migrations, and query optimization. Demonstrable experience designing and owning Playwright E2E test automation suites. Experience with comparable automation frameworks may also be considered. Experience with CI/CD pipelines, such as GitHub Actions, GitLab CI, or equivalent. Hands-on experience with AWS, particularly ECS/Fargate, RDS, and S3. Experience working in a Terraform-managed environment. Demonstrated experience using AI tools in software development, including coding, debugging, planning, or workflow automation. Strong problem-solving, communication, and collaboration skills. Ability to work comfortably with an Australian-timezone team. Nice-to-Have Qualifications: Experience with Terraform or Infrastructure as Code (IaC). Background in B2B SaaS, fintech, accounting, tax, or other financial software. Experience with multi-tenant architecture. Experience implementing SSO, Entra ID, OAuth, or similar authentication solutions. Familiarity with ISO 27001 or other compliance-aware development environments. Experience working in small, founder-led engineering teams.