Software we build.
Systems we break.
Lussy is a UK engineering company. We build dependable software and test it the way real attackers would.

Build it properly. Then try to break it.
One team that writes production software and attacks it for a living, so security is part of the work from day one.

Software development
Web platforms, APIs, internal tools and mobile backends. Designed, built, tested and supported by the same people.
Software servicesPenetration testing
Web apps, APIs, mobile, cloud and networks, tested by hand.
Security audits
Configuration reviews and gap analysis against ISO 27001 and Cyber Essentials.

Secure code review
Line-by-line review of the code that handles money, identity and data.
Cloud and DevOps
CI/CD pipelines, infrastructure as code and hardened cloud accounts on AWS, Azure, GCP and Cloudflare.
Our product
CloakAI, the real-time AI interview assistant.
It listens to interview questions and shows structured answers on a private overlay in under two seconds.
About CloakAI1,870ms
120
Audio captured
640
Transcribed
1,480
Answer reasoned
1,870
On your screen
Pipeline timings published on cloakai.me.
How every engagement runs

Scope
A fixed written scope, timeline and price before any work starts. No open-ended retainers.
Build
Short cycles with working software you can use every week, reviewed for security as it is written.
Test
Manual testing by people who think like attackers, with every finding reproducible.
Support
Documentation, handover and retesting. We stay available after launch if you want us to.
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A penetration test report is only useful if your team can act on it. Here is what to expect in each section, and the warning signs of a weak report.
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A practical checklist for your first penetration test covering scope, access, environments and communication, so testing time finds real issues.
penetration testing
Have something to build, or something to test?
Tell us what you are working on. We reply within one working day with next steps and an honest view of whether we are the right fit.