Senior Software Engineer (AI)

About Us

Sophos is a cybersecurity leader defending 600,000 organizations globally with an AI-driven platform and expert-led services. Sophos meets organizations wherever they are in their security maturity and grows with them to defeat cyberattacks. Its solutions combine machine learning, automation, and real-time threat intelligence with frontline human expertise from Sophos X-Ops to deliver advanced, 24/7 threat monitoring, detection, and response.

Sophos offers industry-leading managed detection and response (MDR) alongside a comprehensive portfolio of cybersecurity technologies — including endpoint, network, email, and cloud security, extended detection and response (XDR), identity threat detection and response (ITDR), and next-gen SIEM. Together with expert advisory services, these capabilities help organizations proactively reduce risk and respond faster, with the visibility and scalability needed to stay ahead of evolving threats.

Sophos goes to market with a global partner ecosystem, including Managed Service Providers (MSPs), Managed Security Service Providers (MSSPs), resellers and distributors, marketplace integrations, and cyber risk partners, giving organizations the flexibility to choose trusted relationships when securing their business. Sophos is headquartered in Oxford, U.K. More information is available at www.sophos.com.

Role Summary

Sophos Firewall is the flagship product of Sophos, operating in the network security domain to protect customer network traffic when deployed in router or switch mode.

As part of the NSG Engineering Group, you will join the Firewall Assistant team in a senior capacity. This team focuses on leveraging AI to interpret natural language queries, deliver intelligent recommendations, and automate firewall operations while upholding enterprise-grade security and compliance standards. The team’s vision is to evolve firewall management from a complex, error-prone manual process into an intuitive, conversational experience—enabling security teams to operate with greater speed, accuracy, and confidence.

What You Will Do

• Own and deliver the production AI harness (assistant-style features: agent loop, tools, guardrails, and evaluations) while driving developer automation and large-scale migration work.
• Take ownership of end-to-end systems and not prompt-only or notebook-only work.

What You Will Bring

• 7-8 years of software engineering experience.
• Hands-on experience with at least two of the following languages: Python, Go, or Java, including the ability to read and modify code beyond your primary language when needed.
• Experience building and deploying production-grade agents using frameworks such as LangGraph, Claude Agent SDK, OpenAI Agents, or Pydantic-AI, including tool integrations, MCP servers (e.g., FastMCP), and multi-agent orchestration. Familiarity with Temporal, Pydantic, FastAPI, and related ecosystems is highly valued.
• Proven experience designing and owning end-to-end distributed systems, including APIs, data models, storage strategies, caching, queuing, and handling failure scenarios and scalability challenges.
• Strong foundation in computer science fundamentals such as data structures, concurrency, networking, and databases, with the ability to reason clearly about latency, throughput, and consistency trade-offs.
• Ability to write clean, testable, and maintainable code, with a focus on robust API design, backward compatibility, and operational excellence.
• Demonstrated experience developing evaluation frameworks, tracing mechanisms, and regression safeguards for LLM-based systems.

Good To Have Skills

• Experience building evaluation frameworks, tracing systems, and regression safeguards for LLM-based applications, beyond reliance on vendor-provided tools.
• Familiarity with prompt caching, KV-cache optimization, model routing, and context engineering to improve cost efficiency and system reliability.
• Experience fine-tuning models (e.g., LoRA, QLoRA, SFT, DPO) for real-world use cases, with measurable improvements in quality — considered a strong differentiator.
• Exposure to deploying solutions across on-premises, cloud, and hybrid environments, with an understanding of constraints, networking, identity, and upgrading cycles.
• Hands-on experience with AWS and large-scale cloud deployments, including infrastructure as code (IaC), networking, identity management, observability, cost/performance optimization, and safe rollout practices.
• Understanding of high-volume telemetry and alerting patterns, along with safety mechanisms for agent-driven actions such as approvals, dry runs, blast-radius control, and audit trails.

Ready to Join Us?

At Sophos, we believe in the power of diverse perspectives to fuel innovation. Research shows that candidates sometimes hesitate to apply if they don't check every box in a job description. We challenge that notion. Your unique experiences and skills might be exactly what we need to enhance our team. Don't let a checklist hold you back – we encourage you to apply.

What's Great About Sophos?

• Sophos operates a remote-first working model, making remote work the primary option for most employees. However, some roles may necessitate a hybrid approach. While we are a remote first organization, applicants must have legal authorization to work in the jurisdiction where the position is posted, without requiring employer sponsorship.
• Our people – we innovate and create, all of which are accompanied by a great sense of fun and team spirit.
• Employee-led diversity and inclusion networks that build community and provide education and advocacy.
• Annual charity and fundraising initiatives and volunteer days for employees to support local communities.
• Global employee sustainability initiatives to reduce our environmental footprint.
• Global fitness and trivia competitions to keep our bodies and minds sharp.
• Global wellbeing days for employees to relax and recharge.
• Monthly wellbeing webinars and training to support employee health and wellbeing.

Our Commitment To You

We’re proud of the diverse and inclusive environment we have at Sophos, and we’re committed to ensuring equality of opportunity. We believe that diversity, combined with excellence, builds a better Sophos, so we encourage applicants who can contribute to the diversity of our team. All applicants will be treated in a fair and equal manner and in accordance with the law regardless of gender, sex, gender reassignment, marital status, race, religion or belief, color, age, military veteran status, disability, pregnancy, maternity or sexual orientation. We want to give you every opportunity to show us your best self, so if there are any adjustments we could make to the recruitment and selection process to support you, please let us know.

Data Protection

If you choose to explore an opportunity, and subsequently share your CV or other personal details with Sophos, these details will be held by Sophos for 12 months in accordance with our Privacy Policy and used by our recruitment team to contact you regarding this or other relevant opportunities at Sophos. If you would like Sophos to delete or update your details at any time, please follow the steps set out in the Privacy Policy describing your individual rights. For more information on Sophos’ data protection practices, please consult our Privacy Policy Cybersecurity as a Service Delivered | Sophos

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.

Key skills/competency

• Senior AI Software Engineer
• Python, Go, Java
• LangGraph, Claude Agent SDK, OpenAI Agents
• Distributed Systems Design
• Computer Science Fundamentals
• API Design
• LLM Evaluation Frameworks
• AWS Cloud Deployments
• Cybersecurity
• Network Security