Here Comes the Sludge with Kelly Shortridge and Josiah Dykstra

Users, threat actors, and the system design all influence—and are influenced by—one another. To design safer systems, we first need to understand the players who operate within those systems. Kelly Shortridge and Josiah Dykstra exemplify this human-centered approach in their work. In this episode we talk about:

• The vital role of human factors in cyber-resilience—how Josiah and Kelly apply a behavioral-economics mindset every day to design safer, more adaptable systems.
• Key cognitive biases that undermine incident response (like action bias and opportunity costs) and simple heuristics to counter them.
• The “sludge” strategy: deliberately introducing friction to attacker workflows to increase time, effort, and financial costs—as Kelly says, “disrupt their economics.”
• Why moving from a security culture of shame and blame to one of open learning and continuous improvement is essential for true cybersecurity resilience.

Kelly Shortridge is VP, Security Products at Fastly, formerly VP of Product Management and Product Strategy at Capsule8. She is the author of Security Chaos Engineering: Sustaining Resilience in Software and Systems.

Josiah Dykstra is the owner of Designer Security, human-centered security advocate, cybersecurity researcher, and former Director of Strategic Initiatives at Trail of Bits. He also worked at the NSA as Technical Director, Critical Networks and Systems. Josiah is the author of Cybersecurity Myths and Misconceptions: Avoiding the Hazards and Pitfalls that Derail Us.

During this episode, we reference:

Josiah Dykstra, Kelly Shortridge, Jamie Met, Douglas Hough, “Sludge for Good: Slowing and Imposing Costs on Cyber Attackers,” arXiv preprint arXiv:2211.16626 (2022).

Josiah Dykstra, Kelly Shortridge, Jamie Met, Douglas Hough, “Opportunity Cost of Action Bias in Cybersecurity Incident Response,” Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 66, Issue 1 (2022): 1116-1120.