Principal Software Engineer

About Checkbox

Checkbox is a Sequoia-backed Series A technology start-up based in Sydney, dedicated to revolutionising in-house legal operations through an AI-centred platform. Our solutions are used by prominent in-house legal teams from companies such as SAP, Coca-Cola, Allianz, BMW, Elastic, and Stryker. We are expanding beyond workflow automation towards AI-powered intake, matter management, triage, and work orchestration, aiming to be the Legal Service Hub for modern enterprises.

Role Overview

We seek a hands-on Principal Engineer to serve as the senior technical authority guiding Checkbox's product engineering efforts, especially in implementing our emerging AI architecture. This role is pivotal in shaping and governing key technical decisions that define the product's future architecture, particularly irreversible, high-impact choices that require careful oversight beyond individual teams. The Principal Engineer ensures architectural coherence, security, and scalability across all engineering streams as the platform expands.

Key Responsibilities

• Lead and own critical architectural decisions, including one-way-door decisions across product engineering streams.
• Define, document, and oversee governance of future-state product architecture.
• Maintain architectural consistency across product teams, platform, data engineering, QA, and enterprise IT.
• Design and implement initiatives that significantly boost engineering productivity and software quality.
• Contribute hands-on code to production releases and uphold high technical standards through example.
• Drive decisions using measurable quality metrics, data, and feedback loops instead of opinions alone.
• Integrate fitness functions, architecture metrics, and feedback mechanisms into development processes.
• Collaborate closely with Data Engineering on data and AI reference architecture.
• Ensure tenancy, security, and compliance considerations are integrated from the outset.
• Partner with Product, Customer Success, and Sales teams to align architecture with customer and business requirements.
• Assist teams in making balanced technical trade-offs regarding speed, scalability, quality, security, and maintainability.

Candidate Profile

• Extensive experience as a Principal Engineer, Staff Engineer, Architect, or senior technical leader in contemporary SaaS settings.
• Deep expertise in product engineering, platform architecture, distributed systems, and cloud-native software.
• Proven capability to make and govern significant architectural decisions across multiple teams or products.
• Track record of delivering initiatives that enhance engineering velocity, quality, or system reliability.
• Comfortable with hands-on production contributions alongside setting technical direction.
• Thorough understanding of tenancy models, security, compliance, and data isolation within enterprise SaaS environments.
• Experience collaborating with platform, data, QA, infrastructure, and enterprise IT teams.
• Strong product and customer insight, connecting technical decisions to business and user outcomes.
• Ability to influence through expertise, clarity, and coding excellence without formal managerial authority.
• Excellent communication skills for effectively engaging both technical and non-technical stakeholders.
• Pragmatic and hands-on approach suitable for a dynamic, fast-growing scale-up environment.

Additional Preferred Qualifications

• Experience with AI-native products, agent-based systems, workflow automation, or legal enterprise technology.
• Involvement in architecture design for multi-product SaaS ecosystems or multiple product streams.
• Background in systems leveraging context, retrieval, event-driven architecture, integrations, or AI workflows.
• Collaboration experience with data engineering on AI or data architecture.
• Implementation of engineering fitness functions, architectural decision records, technical standards, or quality metrics.
• Exposure to Series A or B stage companies or high-growth scale-ups.

What Checkbox Provides

• Competitive remuneration package.
• Hybrid work model with onsite team days at our Sydney CBD office.
• Substantial decision-making influence over architecture shaping Checkbox’s technical trajectory.
• Impact across product engineering, platform, data, and AI system domains.
• Opportunity to scale and contribute to an AI-first SaaS platform adopted by leading corporate legal teams.
• Budget allocated for personal learning and development.
• Flexible leave arrangements.
• Company expense and salary sacrifice schemes.
• Office in central Sydney featuring snacks, beverages, premium coffee, and team social events.
• Regular company-wide social gatherings and annual off-site retreats.
• Transparent, flat organisation culture encouraging questions and feedback.