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HackerOne is a global leader in Continuous Threat Exposure Management (CTEM). The HackerOne Platform unites agentic AI solutions with the ingenuity of the world's largest community of security researchers to continuously discover, validate, prioritize, and remediate exposures across code, cloud, and AI systems. Through solutions like bug bounty, vulnerability disclosure, agentic pentesting, AI red teaming, and code security, HackerOne delivers measurable, continuous reduction of cyber risk for enterprises. Industry leaders, including Anthropic, Crypto.com, General Motors, Goldman Sachs, Lufthansa, Uber, UK Ministry of Defence, and the U.S. Department of Defense, trust HackerOne to safeguard their digital ecosystems. HackerOne was recognized in Gartner's Emerging Tech Impact Radar: AI Cybersecurity Ecosystem report for its leadership in AI Security Testing and has been named a Most Loved Workplace for Young Professionals (2024).
HackerOne is at a pivotal inflection point in the security industry. Offensive security is no longer optional - it is the standard for forward-thinking companies that want to build trust and resilience in a world where AI-driven innovation and adversaries are moving faster than ever. With the industry shifting, HackerOne stands apart: we combine the ingenuity of the largest security research community with a best-in-class AI-powered platform, trusted by the world's top organizations.
HackerOne Values
HackerOne is dedicated to fostering a strong and inclusive culture. HackerOne is Customer Obsessed and prioritizes customer outcomes in our decisions and actions. We Default to Disclosure by operating with transparency and integrity, ensuring trust and accountability. Employees, researchers, customers, and partners Win Together by fostering empowerment, inclusion, respect, and accountability.
Senior Software Engineer, Applied AI
Location: Seattle, WA; Austin, TX; Boston, MA; Washington, DC
1 day onsite per week
Position Summary
At HackerOne, we're revolutionizing offensive security by combining human intelligence with artificial intelligence to help organizations build a safer internet. As a Senior Software Engineer on our AI Platform team, you will contribute directly to the development of our next-generation AI security capabilities, including our in-platform AI security agent, Hai. You will help develop AI-powered features that enhance vulnerability discovery, improve security analysis workflows, and expand how thousands of customers detect and respond to emerging threats.
At HackerOne, we embrace a Flexible Work approach that gives us the freedom to do our best work while also fostering the connections and community that make us stronger. Reflecting this philosophy, this is a role targeted for candidates within ~50 miles of Seattle, WA , Boston, Washington DC, or Austin, TX. We believe this balance of proximity and flexibility gives Hackeronies the chance to occasionally come together - fostering collaboration, connection, and in-person moments that enrich our culture - while still preserving the benefits of remote work. Must be able and willing to come to the office once per week (typically Thursdays).
What You Will Do
Success in this role will be accomplished by delivering the responsibilities below in alignment with HackerOne's Talent Principles: AI-First, Change Agility, Data-Driven Decision Making, and First Principles Problem Solving.

• Contribute to evolving our AI security agent Hai, implementing features that enable natural language security insights, improved reasoning, and secure action workflows.
• Build components and services that integrate Agentic AI design patterns like AI Orchestration, Memory systems, RAG, Long horizon tasks, LLM-based models into the HackerOne platform, applying an AI-First approach to enhance vulnerability detection and security automation.
• Implement features for AI red teaming agents and evaluation tools that help identify risks in LLMs and applied AI systems, supporting safer model development.
• Collaborate cross-functionally with Product, Security Research, and Customer Success to translate customer needs into clear engineering requirements and deliverables.
• Develop and integrate APIs that enable secure interactions between AI models, internal services, and third-party systems, adjusting quickly as requirements evolve with Change Agility.
• Use metrics, evaluation data, and telemetry to validate model behavior and improve system performance in alignment with Data-Driven Decision Making.
• Break down complex AI and security problems into smaller, fundamental components, applying First Principles Problem Solving to deliver simple, scalable solutions.
• Stay current with emerging AI security trends, contributing findings and learnings to team discussions and implementation planning.

Minimum Qualifications

• 5+ years of experience as a software engineer
• Must be able and willing to come to the office once per week (typically Thursdays)
• Experience implementing features within production-grade AI or ML systems, including integrating LLMs or generative AI models into applications
• Hands-on experience with ML frameworks such as PyTorch, TensorFlow, or HuggingFace Transformers
• Familiarity with model deployment workflows, evaluation techniques, or MLOps concepts
• Understanding of responsible AI development and basic AI safety considerations

Preferred Qualifications

• Experience contributing to AI development platforms, internal ML tooling, or experimentation workflows
• Exposure to agentic frameworks such as ReAct, AutoGen, LangChain, or Semantic Kernel
• Familiarity with prompt engineering, fine-tuning, RAG architectures, or LLM optimization techniques
• Experience working with cloud AI/ML services (AWS Bedrock, GCP Vertex AI, Azure ML)
• Familiarity with full-stack technologies such as Ruby on Rails, GraphQL, or React-especially for integrating AI capabilities into existing systems

Compensation Bands:
Seattle, WA , Boston, Washington DC, or Austin, TX
$190K - $230K • Offers Equity Options
#LI-HM1
Job Benefits:

• Health (medical, vision, dental), life, and disability insurance*
• Equity stock options
• Retirement plans
• Paid public holidays and unlimited PTO
• Paid maternity and parental leave
• Leaves of absence (including caregiver leave and leave under CO's Healthy Families and Workplaces Act)
• Employee Assistance Program

*Eligibility may differ by country
We're committed to building a global team! For certain roles outside the United States, India, the U.K., and the Netherlands, we partner with Remote.com as our Employer of Record (EOR).
Visa/work permit sponsorship is not available.
Employment at HackerOne is contingent on a background check.
HackerOne is an Equal Opportunity Employer in the terms and conditions of employment for all employees and job applicants without regard to race, color, religion, sex, sexual orientation, age, gender identity or gender expression, national origin, pregnancy, disability or veteran status, or any other protected characteristic as outlined by international, federal, state, or local laws.
This policy applies to all HackerOne employment practices, including hiring, recruiting, promotion, termination, layoff, recall, leave of absence, compensation, benefits, training, and apprenticeship. HackerOne makes hiring decisions based solely on qualifications, merit, and business needs at the time.
For US based roles only: Pursuant to the San Francisco Fair Chance Ordinance, all qualified applicants with arrest and conviction records will be considered for the position.