About | Secured by David

David R. Gillispie

Cybersecurity Engineer

St. Augustine, FL Remote

Application security AI security Cloud & identity Penetration testing Founder, DeepDream Security Adjunct IT instructor

I’m a cybersecurity engineer based in St. Augustine, Florida. My full formal name is David R. Gillispie III, but I use David R. Gillispie for my public portfolio and professional brand.

My work spans application security, AI security, cloud security, identity and access management, vulnerability management, and penetration testing. I focus on finding exploitable weaknesses, validating what is actually real, and turning technical findings into fixes that engineering and business teams can act on.

My current focus includes AI security, penetration testing, Zero Trust architecture across cloud and identity environments, and building vulnerability workflows driven by exploitability and business impact rather than scanner severity scores.

View resume → DeepDream Security ↗ LinkedIn ↗

Where it started

I have been interested in systems, controls, and how things break for as long as I can remember.

When I was a kid, I used to take apart the family computer because I wanted to understand what was inside and how it all fit together. We did not always have reliable internet access, so when I could not get online, I spent time learning Windows, software, hardware, settings, and basic computer concepts on my own.

But I was not just interested in using computers. I was interested in making them do things, testing limits, bypassing restrictions, and figuring out why something failed.

My parents had a screen-time control device connected to the TV. They kept changing the PIN because I kept figuring it out. I would pretend to be asleep while they entered it, memorize the keypad tones, map the sounds back to the numbers, and use that to unlock it later. That was one of my first lessons in how controls fail when the process around them is predictable.

By the time I was around 12, I knew technology was what I wanted to do. Penetration testing gave structure to the thing I was already drawn to: understanding weak points, testing assumptions, and figuring out how to make systems safer after you understand how they fail.

Age 6–10

Took apart computers. Learned Windows, hardware, and software on my own. Broke things, fixed them, tried again.

Early lesson

Controls fail when the surrounding process is predictable. The weakness was never the device. It was the behavior around it.

Age 12

Knew technology was the direction. Penetration testing gave structure to the curiosity about how things fail.

Today

Security engineering, public-safe tools, engineering patterns, and practical fixes through DeepDream Security and a full-time role.

Early Technical Work

I’ve been building and presenting technical projects long before cybersecurity became my career.

2019 National Champion · Anaheim, CA

BPA Network Design Team

I led my Business Professionals of America Network Design Team to a national championship. The competition covered scalable network design, bandwidth planning, secure storage, centralized management, and defending the solution in front of judges.

Lemelson-MIT Excite Award · 2018

TytoTech

I led TytoTech, a Butler Tech student engineering team that developed the TytoModule, an aircraft smart-skin prototype using pressure sensing and motion tracking to detect exterior damage and document wildlife strike risks.

Different projects, same pattern: build something practical, understand the risk, and explain the technical details in a way people can actually use.

Current work

Full-time engineering and independent consulting.

At my day job I work across internal AI security and penetration testing programs. I also run consulting engagements through DeepDream Security. The day job keeps me close to enterprise-scale security operations. The consulting keeps me close to practical problems that smaller teams face.

I also teach networking and cybersecurity as an adjunct instructor at Cincinnati State and serve on the NETA/CSA Program Advisory Board. Teaching sharpens how I explain technical risk: clear enough for non-security stakeholders, detailed enough for engineering teams, practical enough to act on.

This site

A public proof layer, built carefully.

This portfolio exists because security engineering work is hard to show without exposing things that should stay private. The tools, patterns, and notes here are built specifically to be inspectable: no employer data, no client data, no internal screenshots, no NDA-protected details.

Everything uses mock data, generalized patterns, and public-safe tooling. The goal is a record of how I think through security problems, not a record of where I have worked or who I have worked with.