Europe Arbeitnow ·
full-timeSecurity Engineer (detection & Response)
Refractal · London
About Refractal Refractal is an AI security company building the infrastructure organisations need to defend against autonomous AI threats. 2026 has shown that generally capable intelligence is here. The challenge now is modernising security to stop AI-enabled threats, whether they come from internal agents going rogue or from attackers using AI to become more dangerous. Refractal was founded on cybersecurity and AI expertise from MIT, Microsoft, NASA and the U.S. Navy. Our product lets organisations detect AI-enabled threats at low cost without sacrificing detection quality. We take a practical approach to AI risk, combining proven cybersecurity methods with frontier AI security research. Today, we work with governments and organisations that can't afford to get security wrong. We're backed by leading deep-tech and cybersecurity investors and are growing the team to deliver on this mission. The role You'll bring hands-on detection and response experience into Refractal's product. Working with our software and research engineers, you'll draw on your experience writing detection rules, using SIEMs and investigating threats to shape what we build. What you'll do Translate detection and investigation workflows into product requirements, helping engineers understand what security teams need and why. Use your experience with detection rules and SIEMs such as Splunk and Datadog to guide product design and integration priorities. Build realistic examples and test cases that capture attacker behaviour, benign activity and common sources of false positives. Evaluate product outputs for detection quality, useful context and the effort required for an analyst to reach a decision. Work with customers and colleagues to identify gaps, prioritise improvements and check that changes address practical security needs. Success in your first six months You've translated important detection and response needs into clear product requirements and helped deliver improvements. You've built representative test cases that help the team assess detection quality and investigation usefulness. You've established a feedback loop that brings practitioner experience into engineering and research decisions. About you: essential Hands-on experience writing and tuning detection rules, with examples of how you assessed whether they worked. Practical experience using SIEM platforms, including Splunk or Datadog, to query security data and investigate activity. Experience in detection and response, with a clear understanding of analyst workflows, false positives and gaps in security telemetry. The ability to explain security problems to software engineers and translate your experience into requirements and test cases. An interest in building products and a willingness to challenge assumptions using evidence from practical security work. Nice to have Experience contributing to a security product or working closely with software and research engineers. Scripting skills for preparing data, prototyping ideas or creating repeatable security tests. An interest in how AI changes attacker behaviour and the security of autonomous agents. Our values Radical transparency. We believe the best work happens when everyone feels able to give and receive honest, constructive feedback. Public service. We see AI security as a form of public service. Getting the AI transition right means putting the right infrastructure in place to manage the threats that come with it, and our work helps protect the institutions and services society depends on. Fail fast. We test ideas early, seek feedback and learn quickly. We experiment rapidly and change course when something isn't working, without compromising on security. Pragmatism, not dogmatism. We choose approaches based on how well they solve the problem. That means combining established cybersecurity methods with frontier AI research, questioning our assumptions, and changing our minds when the evidence changes. Compensation and benefits Salary: £60,000–£115,000 Competitive equity to share in Refractal's growth Pension contribution Private medical and dental cover Visa and relocation support Compensation: £60K – £115K • Offers Equity • £60K – £115K • Offers Equity Find Jobs in United Kingdom on Arbeitnow
| Role | Security Engineer (detection & Response) |
|---|---|
| Company | Refractal |
| Location | London |
| Type | full-time |
| Compensation | Not disclosed |
| Deadline | Rolling |
Typical process for this type of role
A general guide — the exact steps for this specific listing may vary; check the original posting for details.
- 1ApplicationSubmit your resume through the apply link.
- 2ScreeningRecruiter reviews your background against the role.
- 3AssessmentA technical test, assignment, or coding round, depending on the role.
- 4Interview(s)One or more rounds with the hiring team.
- 5OfferOffer letter with compensation and start date.
Before you apply
0/4More at Refractal
Other jobs at Refractal
- Systems Engineer · London
- Senior Data Scientist · London
- Senior Content And Marketing Manager · London
- Solutions Engineer · London
- Senior Devops Engineer · London
Explore Related Placements
// similar opportunities
You might also like
Senior Security Engineer - Detection And Response
Klaviyo
At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. ...
Senior Security Detection Engineer
Gitlab
GitLab is the intelligent orchestration platform for DevSecOps. GitLab enables organizations to increase developer productivity, improve operational efficiency,...
Security Engineer
Lemfi
LemFi (Series B) is building the go-to financial app for the Global South. Moving to a new country shouldn’t mean starting from zero. That's why our team of 400...
Application Security Engineer
Legal Counsel - 12 Month FTC At Rightmove Greenhouse
Our vision is to give everyone the belief they can make their move. We aim to make moving simpler, by giving everyone the best place to turn to and return to fo...
Application Security Engineer
Pokemoncareers
Get to know The Pokémon Company International The Pokémon Company International manages the Pokémon property outside of Asia and is responsible for brand manage...
Lead Security Engineer
Encord
About us Encord is the universal data layer for AI that helps 300+ AI teams train and run models on the right data. Our platform indexes, curates, annotates, an...