Security expertise grounded in real-world software engineering
Proofline Security helps organisations identify and reduce security risks across source code, connected systems and architecture.
Our work combines software engineering, architecture and cybersecurity expertise. This allows us to assess security in context, from implementation choices and application behaviour to trust relationships, network connectivity and resilience.
Our strongest specialisations are Application Security Services and Architecture Security Services, supported by broader services in application security, threat modelling and enterprise security improvement.
Engineering-led security
Effective security assessment requires more than knowledge of vulnerabilities and tools.
It requires an understanding of how software is designed, developed, deployed and operated. Proofline brings that engineering perspective into every engagement.
This helps us evaluate:
- whether controls work in practice;
- how implementation and architecture decisions create risk;
- how weaknesses could combine into realistic attack paths;
- which improvements provide the most meaningful risk reduction.
Practical and evidence-based
Proofline focuses on clear findings, realistic impact and practical improvement.
We combine manual analysis, technical validation and architectural context to distinguish meaningful weaknesses from generic scan output.
The goal is not simply to identify what is vulnerable, but to explain:
- why the weakness exists;
- how it could be exploited;
- what the wider impact could be;
- how it can be addressed effectively.
Where our expertise comes from
Proofline combines expertise across software engineering, security architecture and cybersecurity. This combination allows us to assess security within the technical and operational context in which systems are actually built and used.
Software engineering
More than twenty years of experience with the design, development and operation of complex software systems, including distributed applications, cloud platforms and business-critical environments.
Architecture and technical leadership
Experience with system architecture, technical decision-making and the coordination of development across teams, services and organisational boundaries.
Cybersecurity
Specialised expertise in secure software development, application security, security architecture, threat analysis and technical risk assessment, supported by a Master’s degree in Cyber Security.
This multidisciplinary background helps us connect implementation details with wider architectural risks, operational constraints and realistic attack paths.
The experience behind Proofline
Proofline Security was founded by Alcuin van Zijl. The experience behind the company includes assignments within large corporate organisations and security-sensitive environments, including the Dutch Ministry of Defence.
This background shapes Proofline’s practical approach: technically thorough, independent and focused on recommendations that can be implemented by the teams responsible for the system.
As Proofline grows, additional specialists may be involved where an engagement requires complementary expertise. All work remains guided by the same principles of technical depth, direct communication, confidentiality and evidence-based assessment.
Need an independent view of your application or security architecture?
Tell us about the system, planned changes or security concerns. We can help determine an appropriate review scope.