Senior Node.JS Developer

Our client is seeking a Senior Node.js Developer to join their Accessibility Audit Engine teams. This is a foundational engineering role at the heart of the platform, responsible for designing and building the systems that power large-scale accessibility audits, rule evaluation, evidence generation, and compliance reporting.

This is not a maintenance role. Our client is looking for a senior engineer who sets a high technical bar, challenges assumptions, and helps drive best-in-class outcomes through strong engineering discipline, architectural clarity, and a focus on long-term quality.

You will play a key role in shaping core platform capabilities that operate at scale across complex digital estates.

Key Responsibilities

Core Engineering

• Design, implement, and maintain high-performance Node.js services supporting accessibility audit engines, rule execution, and reporting pipelines.
• Build scalable, testable, and observable back-end systems capable of running complex audits across large digital properties.
• Own core audit logic, including rule orchestration, result normalization, evidence capture, and traceability.
• Write production-grade code with a strong emphasis on correctness, performance, and maintainability.

Architecture & Quality

• Contribute to system architecture decisions, focusing on modularity, extensibility, and long-term sustainability.
• Establish and uphold best practices around code structure, error handling, logging, and automated testing.
• Proactively identify technical debt and lead efforts to reduce it in a structured, sustainable way.
• Ensure defects are detected early through strong test coverage and disciplined engineering practices.

Team & Delivery

• Act as a senior contributor within Agile / Scrum teams, working in two-week sprint cycles.
• Collaborate closely with front-end engineers, accessibility specialists, and product leadership to translate requirements into robust technical solutions.
• Contribute to the continuous improvement of development processes, tooling, and infrastructure.
• Serve as a technical leader within the audit engine domain, raising standards through example, mentoring, and peer review.

Required Experience

• 5+ years of professional software engineering experience with a strong focus on Node.js.
• Advanced JavaScript expertise and deep understanding of asynchronous programming.
• Proven experience building and operating production-grade APIs and services.
• Strong test-driven development (TDD) discipline.
• Experience working with Jira (or similar) and Git-based workflows.
• Hands-on experience with AWS, including designing or operating cloud-native services.
• Experience with LLM prompt engineering.

Preferred / Nice-to-Have Experience

• Knowledge of accessibility standards such as WCAG and ARIA, or experience with rules-based evaluation engines.
• Experience with distributed systems, background processing, or job orchestration.
• Familiarity with observability tooling, including logging, metrics, and tracing.
• Previous work on platform-level or engine-level systems, rather than only application-layer development.