Software Engineer in Knutsford

At PortSwigger we choose to be in the office five days a week because we believe being on‑site has several key benefits. We see real value in proximity: it enables "high‑bandwidth" communication, speeds up feedback loops, and helps innovation happen naturally through ad‑hoc chats, quick clarifications, and spontaneous problem‑solving. Being in‑person also strengthens our connections and culture. Shared lunches, casual conversations, and day‑to‑day interactions build trust and a social fabric that creates a sense of belonging, something that's simply easier to develop face‑to‑face. It also helps us to maintain a healthy work‑life boundary. Having a dedicated workspace creates a clear separation between professional and personal life, making it easier to switch off at the end of the day.

This isn’t a typical software developer role, and our hiring approach isn’t typical either. We hire with intention, thinking about people in combination rather than in isolation. The people joining now will shape the team’s culture, its ways of working, and the standard of engineering we hold ourselves to. As a product‑mindful software engineer, you’ll have real ownership from day one: the autonomy to shape your work, the freedom to experiment, and the responsibility to deliver meaningful outcomes. PortSwigger products are trusted by hundreds of thousands of (ethical) hackers, developers, and security professionals worldwide. As a profitable, majority founder‑owned company, we build for the long term — investing steadily in our products and our people.

In this role, you’ll help shape the future of web security through the features you design, build, and evolve; thinking not just about how to implement, but what to build and why. We also invest in an environment where engineers can learn fast and work at the edge of what’s possible with AI. That means giving you the time to explore, the right tools and practical support, so you can experiment responsibly, share what you learn, and turn new capabilities into real improvements for users and the team. This is an opportunity to do high‑leverage, high‑impact work in a supportive environment that values both excellence and care. You’ll solve real, complex user problems and ship robust, user‑ready features that deliver measurable impact. More importantly, you’ll be trusted to think boldly, learn fast, share your work early, and make great decisions in service of our users.

What You’ll Do

• Solve complex technical problems with creativity and sound judgment.
• Contribute across the stack (frontend, backend, infrastructure), balancing breadth with depth and adapting quickly to new domains and tools.
• Talk to users and use insights to drive decisions.
• Share your work early and invite input from peers and cross‑functional partners.
• Collaborate with designers, researchers, marketers, and perform pair programming activities with other engineers and AI.
• Proactively seek and give feedback with candour and care, helping create a culture of continuous improvement.
• Role‑model PortSwigger values and raise the bar through your mindset, behaviours, and technical standards.
• Leverage AI tools (e.g. LLMs, agents, copilots, ML APIs) to improve developer workflows and user‑facing features.
• Explore how AI can be meaningfully integrated into our products to solve real‑world security challenges.
• Help shape how the team works — its practices, its rhythms, and its culture. You’re not just inheriting a playbook, you’re contributing to it.

Requirements About You

We’re looking for engineers who care more about outcomes than output — and who understand that the best work happens when a well‑matched team is pulling in the same direction. The individual skills matter. So does how you bring others with you.

Technical Excellence

• You design and implement high‑quality, scalable features from start to finish.
• You make sound architectural decisions and navigate trade‑offs with confidence.
• You create clean abstractions and intuitive designs.
• You build codebases others want to contribute to and evolve.
• You adapt quickly to new tools, frameworks, and domains.

Judgment and Ownership

• You deliver work that matters and strive for excellence.
• You are a safe pair of hands who thrives in ambiguity and enjoys owning a problem end‑to‑end.
• You ask clarifying questions and constructively challenge assumptions to strengthen outcomes.
• You are comfortable prototyping, iterating, and making trade‑offs.

Product Thinking

• You have experience in product‑led or startup‑like teams.
• You think beyond code—curious about users, product strategy, and business impact.
• You work with urgency, prototyping and validating ideas quickly with users to accelerate learning.

Growth and Collaboration

• You show a growth mindset by embracing feedback, seeking challenge, and pursuing continuous learning.
• You thrive on learning new things, from unfamiliar domains to new tools and workflows, and apply them directly to improve outcomes.
• You empower others by bringing empathy, humility, and clarity to team discussions.
• You build strong relationships across functions, supporting peers and celebrating wins together.
• You give constructive feedback effectively, with candour and care.

AI Literacy

• You’re curious about how to apply AI to improve developer experience, user value, or product outcomes.
• You have, in your work or personal time, used and adopted modern AI tools (e.g. LLMs, copilots), treating them as agentic coding partners—knowing when to trust, adapt, or override their outputs to build high‑quality solutions.

Benefits Why Join PortSwigger?

PortSwigger is a place to do the best work of your career—and be yourself while doing it. We combine high expectations with high support, creating a culture where deep thinkers and collaborative builders who share early and invite input can thrive. We believe in rewarding people generously and offer excellent salaries, based on individual skills and contributions.

Purpose and Culture

• A product with global reach and purpose (Burp Suite helps the world to secure the web).
• A culture of radical candour, autonomy, and continuous learning.
• A supportive environment designed to help you grow and do meaningful work.
• Real ownership and a voice in what gets built and how.
• We foster an inclusive and high‑performance culture with a focus on work‑life balance.
• You’ll be part of a humble, supportive, and fun team that values collaboration, humour, and a strong sense of belonging.

Financial and Well‑being Benefits

• 8% employer pension contribution.
• Share options (discretionary).
• Private medical insurance, provided through Bupa with same day virtual GP appointments.
• Life assurance: 4x salary.
• Income protection: full pay for first 6 months of incapacity followed by 75% of salary plus pension contribution.
• 36 days paid time off: 33 days annual leave (including public holidays) + 3 company‑wide recharge days (decided annually). With the additional option to buy or sell days.
• Regular team events, including memorable summer and winter parties.
• Our working hours are flexible, with core hours from 9am to 4pm.

Ready to Apply?

We care more about mindset and potential than perfect CVs. If you’re excited by the idea of product‑focused engineering and a high‑trust, high‑autonomy culture, we want to hear from you. Not sure if you’re the right fit? Apply anyway. You might be exactly who we’re looking for.