charlie.cullen ↗

Charlie
Cullen

Founder & software engineer.
AI systems. Security. Commercial software.

I’m building SellCode.ai, a new home for code licensing. My work spans AI security, data infrastructure, and robotics simulation. Based in San Francisco.

Axiom evolution field journal with a simulated body and generation timeline
AxiomEmbodied evolution
Code licensingAI & data systemsSecurity engineeringSimulation & robotics
01

SellCode.ai

Founder · September 2026–Present

CURRENT VENTURE

A new home for code licensing.

I founded SellCode.ai to explore new ways for developers to monetize their code. The coming-soon site is live, with a waitlist for launch updates.

02

Inspect the work.

Four projects · actual application captures

A closer look at the systems I’m building. Open a capture to see the full interface, or inspect the demo notes below.

AI Security Agents coursework interface showing three defensive examples and its offline demo status.

01 / AI security coursework

AI Security Agents

Inspect three defensive prompts, record expectations, and verify SQLite parameter binding locally. Built for my Open Avenues coursework.

In progress · offline foundation

Inspect demo

The Assignment 1 interface has three examples, prompt inspection, and support for downloading an experiment plan. A local SQLite check verifies the binding example. Live Gemini responses are still pending; this is the foundation for a security agent.

Orbit’s Carson refinery dossier showing its HOLD decision, historical sources, and 2014 fuel mix.

02 / Evidence and diligence

Orbit

Choose a facility, inspect its sources and fuel mix, and export an evidence dossier from structured energy records.

Historical data · decision on hold

Inspect demo

The Carson refinery capture uses 2014 records. Three sample facility dossiers support Markdown and JSON exports. Each remains on HOLD because the historical records do not establish current decision evidence.

Axiom’s simulated quadruped after a completed flat-ground trial, with distance, tilt, and elapsed simulation time visible.

03 / Robotics simulation

Axiom

Build a quadruped, test movement controllers, and replay a trial through a 3D interface backed by Rust physics.

3D simulation · software trials

Inspect demo

The capture shows a completed flat-ground trial with movement and stability measurements. Body settings and controller choices can be compared through repeatable simulations and replays. The parameters have not been calibrated against physical hardware.

Myth’s modeled OIDC containment comparison showing projected paths changing from seven to two.

04 / Causal security analysis

Myth

Trace an evidence chain and compare containment choices in a security investigation workbench.

Fictional scenario · modeled outcomes

Inspect demo

The bundled Northstar scenario models an OIDC containment choice and projects reachable paths from seven to two. The comparison illustrates a local model’s outcome; it makes no changes to production systems.

Captured October 5, 2026.

03

Axiom

Robotics evolution simulator

Evolving bodies. Exploring possibilities.

Axiom explores how robot body plans and neural controllers evolve together. Its Rust simulation keeps a diverse archive of candidates, making movement, fitness, and search history visible rather than reducing every experiment to a single winner.

  • Rust
  • Python
  • Bevy
  • Rapier3D
  • MAP-Elites
  • Neural controllers

Body and behavior

Morphology genomes and neural controllers connect the shape of a simulated body with the way it moves.

Diversity in search

A MAP-Elites archive retains different high-performing candidates across terrain tasks.

Inspectable experiments

Seeded runs, checkpoints, and replay interfaces make it possible to revisit an experiment and compare outcomes.

Axiom's evolution field journal showing a simulated creature, fitness history, and search lineage
Axiom’s evolution field journal: a captured simulation interface.
04

What I work on

From research and prototyping to tested, maintainable software.

01

AI systems & data

LLM guardrails, retrieval workflows, NLP post-processing, and structured data pipelines. Python, PyTorch, DuckDB, and FastAPI.

02

Security engineering

Client penetration testing, prioritized remediation, AI governance, and zero-trust architecture. CompTIA Security+ certified.

03

Commercial software

AI-native developer tools and security software, supported by automated CI, tagged releases, and verification pipelines.

04

Simulation & interfaces

Robotics evolution, real-time telemetry, and interfaces that make complex systems understandable. Rust, C++, TypeScript, and React.

My commercial work includes private, licensed software. The highlights here share the problems I work on and the systems I build.

05

Experience & background

Software engineering, applied AI, security, and commercial software.

Experience

  1. Founder

    Sep 2026–Present

    SellCode.ai ↗

    • Founded a software venture focused on new ways to monetize code.
  2. Software Engineer

    Sep 2026–Present

    Independent Software Licensing

    • Develop and license software for AI training, coding evaluation, and software-engineering research.
    • Built a portfolio of 20+ substantial projects across AI, security, infrastructure, simulation, and developer tooling.
    • Generated thousands of dollars in non-exclusive source-code licensing revenue.
    • Maintain reproducible systems with Docker, CI/CD, automated testing, and structured Git history.
  3. Penetration Tester

    Jul–Sep 2026

    CyberTrust America

    • Conducted client penetration tests and delivered prioritized findings with remediation guidance.
    • Tested an AI-governance certification program aligned with NIST AI RMF and NIST CSF.
  4. AI Developer

    Jan–May 2026

    Popaisle

    • Built LLM guardrails for OpenRouter CLI workflows and NLP post-processing.
    • Developed web crawlers to collect, normalize, and deduplicate structured data for client projects.
  5. Computer Science Tutor

    Jan–May 2026

    CCSF Tutor Squad

    • Tutored C++, computer architecture, algorithms, and data structures, with an emphasis on debugging.
  6. AI Developer

    Dec 2025–Jan 2026

    AI Tinkerers

    • Led a four-person team building a commercially licensed energy research assistant.
  7. Software Developer

    Nov 2025–Jan 2026

    CCSF Engineering Club

    • Built VESC-based marine telemetry and reduced latency by more than 30% with WebSockets.

Education

City College of San Francisco

Aug 2025–Present

Computer Science · GPA 4.0

University College Cork

Aug 2023–May 2025

Computer Science

Certifications

CompTIA Security+

2026

DeepLearning.AI

2025

Deep Learning & Machine Learning Specializations; PyTorch for Deep Learning; Mathematics for ML & Data Science.

Applied learning

Open Avenues

Sep–Nov 2026 · In progress

AI Security Agents coursework: Python and Gemini API experiments, defensive prompt evaluation, and local verification of security claims.

Technical skills

Languages
Python, Rust, C++, Go, TypeScript, JavaScript, SQL
AI / Data
PyTorch, NumPy, Pandas, RAG, LangGraph, NLP, vector search
Engineering
FastAPI, REST APIs, DuckDB, WebSockets, Docker, React, Tauri, Git/GitHub, CI/CD
Security
Penetration testing, NIST AI RMF, NIST CSF, zero-trust architecture, LLM guardrails