Senior QA Automation Engineer - Nucleus Security

Overview

We are seeking a detail-oriented and proactive QA Automation Engineer to join our team. This role is responsible for ensuring the quality, reliability, and performance of our applications through a combination of manual and automated testing across front-end and back-end systems.

The ideal candidate is passionate about software quality, enjoys working in a collaborative environment, and is motivated to improve testing processes, tools, and automation coverage.

About Nucleus Security

Nucleus Security is transforming how security and development teams manage vulnerabilities at a scale. Our platform unifies vulnerability data across scanners and environments, enabling organizations to prioritize and remediate vulnerabilities efficiently. Through our integrations, we empower customers to ingest data from their existing tools with minimal setup and maximum reliability.

Core Responsibilities

What You Will Do

• Ensure the quality and reliability of assigned products across the full stack - UI, APIs, and data - defining test approach and risk coverage with the QA Manager, and leveraging AI tools to improve coverage and efficiency
• Build, extend, and improve scalable automation frameworks in Selenium and Playwright that the team relies on, reducing manual testing effort and increasing confidence in every release
• Act as a quality advocate within the team - reviewing test code, sharing testing practices with peers, and raising design concerns early enough to prevent defects rather than catch them

Testing & Quality Assurance

• Plan and execute test coverage for complex, cross-system features, including functional, regression, smoke, integration, and end-to-end testing
• Design and execute manual and automated test cases covering functionality, performance, and reliability, including positive, negative, and edge cases
• Assess risk and prioritize testing effort, making clear recommendations on depth of coverage versus delivery timelines
• Map test cases to business requirements and functional designs, ensuring traceability and identifying gaps before development begins
• Investigate complex or intermittent failures to root cause, distinguishing product defects from test instability and environment issues
• Document and report defects, verify fixes, and ensure timely resolution in collaboration with development teams

Database & Data Validation

• Write and execute complex SQL queries to validate data integrity, transformations, and business logic across the application stack
• Verify data accuracy through ingestion, normalization, and processing workflows - record counts, deduplication, field-level mapping, and malformed or partial data
• Validate database interactions triggered by UI and API operations, and test data migrations, schema changes, and backfills for correctness and backward compatibility
• Build and maintain reusable test data sets and database setup and teardown routines for reliable, repeatable automated runs

Automation & Frameworks

• Implement and review automated test scripts using Java with Selenium WebDriver and Playwright, following best practices such as the Page Object Model
• Contribute to the architecture and long-term health of automation frameworks - structure, reusable components, reporting, and test data management
• Incorporate database validation into automated suites through query-based assertions and programmatic test data setup
• Improve automation reliability by reducing flakiness, execution time, and maintenance cost as suites grow
• Integrate automated tests into CI/CD pipelines and support optimization within DevOps workflows, including parallel execution
• Support performance and scale testing, and recommend tools and processes that measurably improve QA effectiveness

AI-Assisted Testing

• Hands-on experience using AI tools for test case generation, test data creation, and defect analysis
• Familiarity with Model Context Protocol (MCP) tooling, such as Playwright MCP, for AI-driven browser interaction, exploratory testing, and test script generation
• Experience with AI-assisted coding tools for building and maintaining automation scripts, with sound judgment about where AI output needs human validation
• Ability to apply AI thoughtfully within QA workflows and share what works with the rest of the team

Collaboration & QA Practices

• Partner with the QA Manager, developers, and product managers to clarify requirements and acceptance criteria
• Support and mentor less experienced QA engineers through technical guidance, code review feedback, and knowledge sharing
• Participate in design reviews and technical discussions, surfacing testability and reliability concerns early
• Contribute to continuous improvement of QA processes, tools, and standards across the team

What we’re looking for:

Required

• 8+ years in software quality assurance, with at least 5 years in test automation
• Strong programming skills in Java, with demonstrated ability to write clean, maintainable, reviewable test code
• Hands-on experience with Selenium WebDriver and Playwright, and with design patterns such as the Page Object Model
• Experience contributing to the design or significant refactoring of an automation framework, not just writing tests within one
• Solid API testing experience and strong SQL skills, with hands-on experience validating application behavior directly against relational databases
• Working knowledge of CI/CD tooling and version control, with experience running automation reliably within pipelines
• Strong analytical and debugging skills, with a track record of driving complex issues to root cause

Preferred (Nice to Have)

• Experience working in cybersecurity, vulnerability management, or security-focused products and environments
• Familiarity with security concepts such as vulnerabilities, risk scoring, APIs, and data protection practices
• Experience with MCP servers or agent-based testing workflows beyond basic tool usage
• Experience testing ETL or data pipelines, or working with large-scale or NoSQL data stores
• Experience with performance or load testing, cloud environments, or containerized test infrastructure

Common Skills & Traits

• Self-starter with a strong ownership mindset and the ability to wear multiple hats in a fast-paced environment
• Strong problem-solving and collaboration skills, with the maturity to disagree constructively
• Ability to quickly learn new tools, technologies, and frameworks - and to teach them to others
• Willingness to fail fast, iterate, and improve

Why Nucleus?

• Nucleus is a truly unique solution that’s defining a market AND making an actual impact.
• We’re biased, but you will get to work with one of the best teams in security. We have a lot to get done and we work extremely hard, but we have fun in the process.
• Work with a high-performing team that values creativity, autonomy, and innovation.
• Collaborate on meaningful products that improve the security posture of major organizations.
• Enjoy flexible remote work arrangements and a strong emphasis on work-life balance.