Title: Securing the World´s biggest HR Firm | Martijn Nykerk, CISO at Randstad | Cyber Security District

Episode Description:

What does it take to secure a company that manages the careers of millions of people across the globe?

In this episode of Cyber Security District, we sit down with Martijn Nykerk, CISO at Randstad, one of the world’s largest HR and recruitment firms, with over 6,000 branches across 38 countries. Martijn has spent 20 years inside Randstad, growing from running the Dutch telco infrastructure to becoming its first global CISO, building security from the ground up as the company transformed from a federation of local operators into a true multinational.

With an engineering background forged on North Sea gas platforms, Martijn brings a rare perspective to the CISO role: the ability to zoom in and out across technical, process, organizational, and business layers simultaneously. In this conversation, he breaks down what that actually looks like in practice, why social skills matter more than most security professionals think and how to build a security function that people want to work with.

In this episode, we explore:

• How Martijn’s career started on a North Sea gas production platform and why safety systems are the original cybersecurity
• What it took to build Randstad’s first global security function from scratch
• The CISO dilemma: centralize or embed?
• How to build a security team people actually want to engage with
• Managing vulnerability backlogs, budget battles, and the patching problem
• The real-world incident that moved cybersecurity from priority 43 to priority 1 overnight
• How AI is lowering the barrier for attackers including 16-year-olds running perfect phishing campaigns
• Why CISO community-building and information sharing matter more than ever

Timestamps:

(00:00) – Introduction

(01:15) – Starting on a North Sea gas platform

(05:30) – Joining Randstad and running the Dutch telco infrastructure

(09:00) – Becoming Randstad’s first global CISO

(14:20) – The “zoom in and zoom out” CISO mindset

(19:45) – What would surprise someone shadowing a CISO for a week

(24:10) – Compliance-heavy vs. risk-driven CISO profiles

(28:30) – Embed vs. centralize: the security team structure debate

(33:00) – How to make security a team people want

(37:15) – Patching, vulnerability backlogs, and the budget war

(42:30) – Building a security narrative that lands with leadership

(46:00) – The incident that changed everything: data breach and crisis response

(53:20) – What makes a great security professional (hint: it’s social skills)

(58:00) – The CISO hiring interview: starting with “What questions do you have for me?”

(01:02:10) – Community building and the 80% overlap problem

(01:07:30) – AI as an attacker accelerant

(01:12:00) – Final message to CISOs: trust each other and share more

Connect with the guest:

Martijn Nykerk: https://www.linkedin.com/in/martijnnykerk/

Follow Cyber Security District: Laurens Jagt on LinkedIn: https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com/ All channels & newsletter: https://beacons.ai/cybersecuritydistrict

In this episode of Cyber Security District, we speak with Chris Zadeh, serial entrepreneur, fintech pioneer, angel investor, and author. Chris was founder and CEO of Ohpen, one of the first cloud-native core banking platforms in Europe, orchestrating more than €100 billion in financial flows. After building and scaling Ohpen for ten years, he exited and shifted his focus to investing, launching a dedicated cybersecurity fund and his own investment vehicle.

From growing up without financial privilege to becoming one of the early digital banking pioneers at Binck in the Netherlands, Chris shares an unfiltered look at execution, obsession, discipline, and what it truly takes to win in regulated markets. Now Chris is investing in cybersecurity startups, Chris explains what he looks for in founders, why AI is reshaping risk and compliance, and why Europe must rethink digital sovereignty.

In this episode, we cover:

• Chris’ founder journey: from Binck Bank scale-up years to building Ohpen for 10 years
• What “security-first” looks like in fintech, non-negotiables, resilience, and trust with enterprise buyers
• Execution culture, exceeding expectations, hiring for discipline, and why culture beats product
• The shift to investing and why he started a cyber fund and what he looks for in founders
• What’s next in AI-driven risk, compliance + security convergence, and Europe’s digital sovereignty challenge

Timestamps: 00:00 – Intro 00:14 – Meet Chris Zadeh 01:59 – Growing up without financial safety nets 03:14 – Joining BinckBank at 23 06:52 – Scaling to market dominance 08:57 – Wanting to sit at the decision-making table 11:36 – Early infrastructure and security lessons 14:18 – A firewall shutdown incident 17:55 – Leaving to build Open 18:48 – The vision for cloud-native core banking 22:29 – 744 pages of rejection before first contract 27:14 – Migrating €15B live 28:09 – Security as non-negotiable 32:15 – Hiring discipline and execution mindset 35:05 – Culture: exceed expectations or leave 37:35 – The cost of extreme execution 41:21 – Transitioning to investing 44:27 – Why he rejects the “solo entrepreneur” myth 49:35 – Launching the cybersecurity fund 51:16 – AI, compliance, and new cyber opportunities 58:55 – European cloud sovereignty 01:04:03 – Signal message to CSOs: stay curious 01:06:00 – Outro

Connect with the guest: Chris Zadeh: https://www.linkedin.com/in/chriszadeh/ Dark Red (Cyber Fund): https://www.darkred.at/

Follow Cyber Security District: Laurens Jagt on LinkedIn: https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com/ All channels & newsletter: https://beacons.ai/cybersecuritydistrict

What if the real cybersecurity crisis isn’t attackers, but our own backlog?

In this episode of Cyber Security District, we sit down with Jaya Baloo, former CISO at major global organizations including KPN, Avast, and Rapid7 and now founder of AISLE™, an AI-native platform designed to not just detect vulnerabilities, but fix them.

After years defending complex enterprises from relentless threats, Jaya made a bold move: stepping out of the CISO seat to build the kind of technology she wished she had. Her mission is clear, eliminate the massive vulnerability backlog that leaves organizations trapped in “security theater” instead of meaningfully reducing risk.

This conversation goes beyond buzzwords. We unpack why detection without remediation is broken, how AI can be applied responsibly to actually close security gaps, and what it takes to build transformative security products in stealth.

In this episode, we explore:

• Why Jaya left top-tier CISO roles to start AISLE™
• The uncomfortable truth about vulnerability backlogs and unpatched systems
• Why identity failures remain a systemic weakness
• How AISLE uses AI for detection, remediation, and verification
• The importance of stealth mode before going public
• What leadership looks like in an AI-driven cybersecurity era

Key Takeaways:

• Vulnerability management without remediation is incomplete
• Security technical debt is evolving into a societal-level risk
• AI must be paired with verification and human oversight
• Innovation is essential to preserving true defence in depth
• The best CISOs stay curious and challenge their own assumptions

Timestamps: 00:00 – Introduction 01:20 – Jaya’s transition from enterprise CISO to founder 05:45 – The vulnerability backlog problem 10:30 – Why identity failures remain systemic 16:40 – Building AISLE™: from concept to stealth 22:15 – AI for remediation, not just detection 29:50 – Verification, testing, and human-in-the-loop controls 36:10 – Working with design partners and open-source communities 42:35 – The AI shift in cybersecurity 48:20 – Leadership lessons from the CISO seat 54:10 – Final message to global CISOs

Connect with the guest: Jaya Baloo: https://www.linkedin.com/in/jaya-baloo-558492/

Website: https://aisle.com/

Follow Cyber Security District: Laurens Jagt on LinkedIn: https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com/ All channels & newsletter: https://beacons.ai/cybersecuritydistrict

In this episode of Cyber Security District podcast, we speak with Marco Ramilli, a cybersecurity visionaire, TEDx speaker, and founder of IdentifAI, a deepfake detection company working at the intersection of AI, trust, and digital identity. From writing early sandboxing papers to leading cyber defense teams and selling his previous startup to VirusTotal (Google), Marco has spent the last two decades safeguarding digital borders.

At IdentifAI, he’s now taking on one of the biggest threats of the AI era: manipulated content. Whether it’s fake insurance claims, fraud in football scouting, or synthetic identities onboarding to banks, his platform uses AI to detect AI: verifying whether images, voices, or videos were generated by humans or machines.

In this episode, Marco shares his founder story, why he believes the shift from deterministic to probabilistic computing will reshape cybersecurity, and how his latest startup scaled to enterprise use cases within a year.

• Marco’s hacking origin story and first run-in with his university
• Researching malware and voting systems at UC Davis
• Founding his first cybersecurity company in Italy when the market wasn’t ready
• Bootstrapping a business through 3+ years of break-even before momentum hit
• Early ransomware response and reverse-engineering threats
• Getting acquired by Tinexta and integrating into VirusTotal
• Building IdentifAI to detect deepfakes using AI-powered forensics
• From onboarding fraud to football scouting scams, real use cases
• The rise of “digital performers” and the ethics of synthetic content
• Why deterministic cybersecurity tools are no longer enough
• The philosophical shift security teams must make to handle probabilistic models
• Advice for scaling startups, hiring A-players, and letting go as a founder
• His signal message to CISOs: curiosity will save us

00:00 – Intro 00:14 – Meet Marco Ramilli 01:00 – Hacking the campus network (with a for loop!) 02:15 – Getting caught, and hired for cyber research 03:10 – Reverse engineering malware at UC Davis 04:30 – Cybersecurity in Italy: too early, too expensive 05:45 – Why compliance was seen as a cost 06:20 – Building a company just to be the “owner of his time” 07:00 – Early business struggles & staying focused 08:30 – Why saying “no” saved his startup 10:10 – On embracing failure and learning from loss 11:30 – Curiosity, discomfort, and moving to the U.S. 13:00 – Sleeping on floors and working without backup 14:00 – Founding Yoroi, growing from 4 to hundreds of employees 15:30 – The ransomware era and massive inbound traction 16:45 – Sandboxing: research, papers, and real-world applications 18:00 – Joining Google via acquisition 19:30 – Startup phases and letting go as a founder 21:00 – Hiring advice: don’t save money on great people 23:00 – Launching IdentifAI: how a fake Pope jacket sparked a real mission 25:00 – Building AI to detect AI: early model design 27:00 – From 80% to 96% accuracy in deepfake detection 28:00 – Why images are more dangerous than text 29:45 – The weaponization of synthetic media 31:20 – How IdentifAI detects voice, image, and video manipulation 32:45 – Use cases: banking KYC, insurance fraud, and football scouting 35:00 – API-first strategy and enterprise readiness 36:30 – “Digital Performers” and the ethics of representation 37:30 – Real-time meeting detection via agents 39:00 – Why probabilistic AI is changing the rules 40:00 – How cybersecurity must evolve to deal with uncertainty 43:20 – Deployment flexibility: on-prem or private cloud 46:20 – The philosophical challenge of non-deterministic systems 49:30 – Final message to CISOs: stay curious

Connect with the guests:

• Marco Ramilli: https://www.linkedin.com/in/marcoramilli/
• Website: https://identifai.net/

Follow Cybersecurity District:

• Laurens Jagt on LinkedIn: https://www.linkedin.com/in/laurensjagt/
• Website: https://www.cybersecuritydistrict.com/
• All channels & newsletter: https://beacons.ai/cybersecuritydistrict

In this episode of Cyber Security District, we sit down with Kim van Lavieren, co-founder and CTO of Dawnguard, a cybersecurity startup that raised millions in funding before registering a company or launching a product. Kim’s story is anything but ordinary, from leading Marines on no-sleep missions to building offensive hacking tools for the Dutch military, to managing massive security teams at Amazon in the U.S., his path combines discipline, vision, and deep technical mastery.

Together with co-founder Madi Abdurazak, Kim is now on a mission to completely rethink how cybersecurity should be done, by starting not with alerts or vulnerabilities, but with architecture, policy, and real business risk. Dawnguard is building a platform that automates secure-by-design architecture using AI, aiming to replace an entire category of cloud security tools before most companies even realize there’s a better way.

• What the Dutch Marine Corps taught Kim about discipline and decision-making
• How a military comms officer became a cybersecurity architect
• Building secure systems after discovering flaws in weapons room access
• Writing offensive tools for the cyber division of the Dutch Armed Forces
• Why cyber soldiers may be more impactful than boots on the ground
• Kim’s journey to Amazon and running third-party security at massive scale
• The mindset shift from “no” to “how” in security engineering
• The origin story behind Dawnguard and raising millions pre-product
• How Dawnguard is building a new category for architecture-led security
• Using AI to design, verify, deploy, and enforce security from day zero
• Advice for cybersecurity newcomers, and why the industry must rebrand
• How Dutch risk aversion is holding back innovation — and how to break through

00:00:00 – Intro 00:00:47 – Kim's Background: From Marines to Cybersecurity 00:03:29 – Training Under Extreme Pressure 00:06:28 – Becoming a Communications Officer & Discovering Security Gaps 00:08:18 – First Lines of Code at Age 10 00:10:19 – When Tech & Physical Endurance Collide 00:11:04 – Offensive Cyber Capabilities in the Military 00:14:22 – Why Cyber Soldiers Now Matter More Than Physical Ones 00:17:05 – Consulting, CISO Roles & Joining Amazon 00:18:49 – The Scale & Speed of Security at Amazon 00:21:00 – The Origin of Dawnguard 00:23:00 – Automating Architecture Compliance with AI 00:25:08 – Using Threat Intel & Policy as a Starting Point 00:28:02 – Building the Engine: 5 AIs and a Moonshot 00:30:46 – Meeting Madi & Finding the Perfect Co-Founder Match 00:33:29 – Raising Millions with No Product — and Building a Dream Team 00:36:37 – Rise Into Resilience: What the Dawnguard Slogan Really Means 00:38:08 – Rebranding Cyber: Why the Industry Needs a Makeover 00:39:44 – Advice for People Trying to Break Into Security 00:41:03 – Advice for Aspiring Cyber Entrepreneurs 00:44:42 – Certifications, Labs & Reality Checks 00:47:25 – Going Big Means Accepting Uncertainty 00:49:00 – The 5-Year Vision: Replace Entire Security Categories 00:50:30 – Final Signal Message to CISOs: Security Is Balance, Not Absolutes

Connect with the guests:

Kim van Lavieren: https://www.linkedin.com/in/kim-v-0645931b4/

Learn more about Dawnguard: https://dawnguard.ai/

Follow Cyber Security District: Laurens Jagt (Host): https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com All channels & newsletter: https://beacons.ai/cybersecuritydistrict

In this episode of Cyber Security District, we sit down with Niek Waarbroek (Founder & CTO) and Tycho Klessens (CEO) of Florbs, a Dutch startup transforming file security inside Google Workspace. What started as a simple set of admin scripts has evolved into a powerful SaaS platform, used by global enterprises to automate onboarding, offboarding, and prevent accidental (or malicious) data leaks.

Niek shares how his frustrations with error-prone onboarding flows inspired him to build smarter tools, and how a lack of visibility into shared files became a real security threat for many organizations. After bootstrapping Florbs for three years, he crossed paths with Tycho, then a VC investor, who not only became the commercial co-founder, but helped raise €1 million to scale the team.

Together, they discuss the power of building with product-led growth, how they’re scaling without wasting capital, and why real file security goes beyond Google’s default settings. They also explain why early-stage cybersecurity startups need more than funding, including focus, clarity, and the right partner chemistry.

In this episode, we cover:

• The original problem Florbs set out to solve inside Google Workspace
• Why offboarding is one of the biggest overlooked security gaps
• How ex-employees still access company data without detection
• From custom scripts to a full-fledged SaaS product
• Product-led growth without a sales team or marketing budget
• Raising €1 million from angel investors and CISOs
• Going from solo founder to building a complementary co-founder team
• How they’re building safe, reversible file actions with real-time insights
• Expanding into AI-powered detection and cross-platform collaboration security
• Lessons learned transitioning from VC investor to cybersecurity CEO

Whether you're a CISO, founder, or operator working in Google Workspace or building a startup yourself, this episode shows how automation and visibility can finally close one of the biggest blind spots in modern file security.

Timestamps: 00:00 – Intro 01:15 – What Inspired Florbs: The Google Workspace Problem 03:40 – Why Onboarding & Offboarding Create Risk 06:00 – Real-World Cases: Ex-Employees Accessing Confidential Docs 08:45 – Building from Admin Scripts to Full Product 11:30 – Why Google Alone Doesn’t Cut It for File Security 14:50 – The Origins of the Name “Florbs” 18:10 – Google Developer Expert Status & Product-Led Growth 21:00 – Meeting Tycho: From VC Investor to Co-Founder 25:30 – The First Pitch, the Missed Investment & The Unexpected Partnership 30:40 – Raising Smart Capital (Not Just Any Capital) 34:00 – Scaling Carefully: Where the €1M Will Go 37:20 – Building Automated Security Workflows 40:15 – Preventing AI-Fueled Phishing & Lookalike Domain Attacks 44:00 – Hiring Philosophy, Co-Founder Chemistry & Startup Reality 49:00 – Final Advice for Entrepreneurs & First-Time CISOs 52:30 – One Signal Message to CISOs: Don’t Block Everything

Connect with the guests:

Niek Waarbroek: https://www.linkedin.com/in/niekwaarbroek/

Tycho Klessens:https://www.linkedin.com/in/tycho-klessens-a215abb7/

Learn more about Florbs: https://florbs.io

Follow Cyber Security District: Laurens Jagt (Host): https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com All channels & newsletter: https://beacons.ai/cybersecuritydistrict

In this episode of Cyber Security District, we sit down with Seemant Sehgal, founder and CEO of Breachlock, one of the fastest-growing offensive security companies in the world. Seemant’s journey took him from a small town in Northern India to leading global cybersecurity teams at ING Bank, before founding a startup that’s now active in over 20 countries.

At Breachlock, Seemant is rethinking how offensive security is done. His platform combines automation, AI, and human-led red teaming to deliver scalable Pen Testing as a Service (PTaaS) that addresses the growing inefficiencies of traditional penetration testing.

Seemant has built a globally distributed company operating in over 20 countries, while staying close to the ground truth of cyber operations and keeping his team deeply connected to the challenges that security teams face every day.

In this episode, we cover:

• Building a global cyber career without a linear path
• Lessons from running cybersecurity at ING Bank
• The inefficiencies of traditional pen testing
• Starting BreachLock with automation and AI at the core
• Launching Adversarial Exposure Validation (AEV)
• Balancing AI and human expertise in offensive security
• Leading a remote team across 20+ countries
• Hiring for culture and alignment, not just skills
• How to sell cyber risk to non-technical stakeholders
• Message to all CISOs

Whether you're scaling a security startup, running a blue team, or navigating board-level cyber strategy, this episode delivers hard-earned insights from someone who's seen the full lifecycle, technical, strategic, and entrepreneurial.

Timestamps: 00:00 – Intro 01:10 – Growing Up in Northern India 03:25 – Starting Out in Ethical Hacking at IBM 06:10 – From Defense to Offense: Career at ING Bank 09:00 – Identifying the Pain Points of Traditional Pentesting 11:30 – Founding BreachLock: Automating What Matters 15:40 – What is Adversarial Exposure Validation (AEV)? 19:20 – Scaling with AI, But Keeping It Human 23:45 – Managing a Remote-First Global Team 26:30 – Hiring Philosophy: Look for Disagreement and Culture Fit 30:15 – Translating Cyber Risk for the C-Suite 33:00 – Staying Grounded: Lessons from Building Profitably 36:20 – Advice to Future Founders & Security Leaders 39:00 – Final Message to all CISO’s

Connect with the guest: Seemant Sehgal: https://www.linkedin.com/in/s-sehgal/ Learn more about Breachlock: https://www.breachlock.com/

Follow Cyber Security District: Laurens Jagt (Host): https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com All channels & newsletter: https://beacons.ai/cybersecuritydistrict

In this episode of Cyber Security District, we sit down with Mischa van Geelen, one of the Netherlands’ most remarkable cybersecurity professionals. At just 13 years old, Mischa discovered a critical vulnerability at a major Dutch bank. By 15, he was the youngest full-time pen tester at a global consultancy. Now in his twenties, he’s already co-founded one of the top incident response firms in the country, served as TISO at leading payment institutions like iDEAL and European Payment Institute (EPI) and is gearing up to launch his next venture.

Mischa’s story is anything but ordinary. A self-taught hacker turned security strategist, he shares candid insights into the realities of incident response, the pitfalls of “watermelon compliance,” and why cybersecurity must be treated as a business enabler, not a sunk cost. Whether it’s rebuilding a college’s IT infrastructure after a massive ransomware attack or scaling a startup from scratch, Mischa combines technical brilliance with rare clarity on communication, compliance, and leadership.

In this episode, we cover:

• Discovering his first vulnerability at age 13
• Interning at ABN AMRO while still in high school
• Joining a consultancy firm as a full-time pen tester at 15
• Building and scaling an incident response company
• Inside stories from real-world cyberattacks
• Why most companies still don’t “get” compliance
• The burnout risk of incident responders
• His thoughts on AI, deepfakes, and the future of cybercrime
• Plans for his next cybersecurity venture
• Advice for aspiring ethical hackers and cyber entrepreneurs

Whether you're a CISO, student, founder, or future threat analyst, this episode is packed with valuable lessons and honest reflections from someone who's lived cybersecurity from every angle and isn't done yet.

Timestamps: 00:00 – Intro 01:00 – Finding His First Vulnerability at 13 04:20 – Interning at ABN AMRO 07:00 – Getting Misunderstood by the School System 09:40 – Joining a Consultancy as a Teenager 14:00 – Launching a Cybersecurity Company at 17 17:20 – Challenges of Managing Incident Response Teams 22:30 – Real-Life Ransomware Incidents 27:10 – The Reality of 24/7 Cyber Incident Response 31:45 – The Emotional Impact of Cybercrime 34:30 – Working with iDEAL & EPI 38:10 – AI Threats and the Rise of Deepfakes 42:00 – Watermelon Compliance & What’s Broken in Cyber 45:50 – Mischa’s Next Venture: Automating Real Compliance 49:20 – Communication as the Missing Skill in Cybersecurity 52:00 – Final Message to Global CISOs

Connect with the guest: Mischa van Geelen: https://www.linkedin.com/in/rickgeex/ Learn more about Anovum: https://www.anovum.nl

Follow Cyber Security District: Laurens Jagt (Host): https://www.linkedin.com/in/laurensjagt/ Website: https://www.cybersecuritydistrict.com All channels & newsletter: https://beacons.ai/cybersecuritydistrict