Last updated: November 3, 2026

Available for Opportunities

Building StopHarbor and Global Ticket Pay. Publishing independent research through Zimmër Trading.

De’Mondre Zimmerman

Software Founder
& Independent Quantitative Researcher

San Antonio, TX

About

I’m De’Mondre Zimmerman, also known as DJ. I build business software and study systematic trading from San Antonio, Texas.

I founded StopHarbor, a route-planning workspace for small field teams, and Global Ticket Pay, a traffic-citation lookup and payment service operated by GTP Systems Inc. My work connects product design, full-stack engineering, and the practical workflows people need to finish.

Through Zimmër Trading, I develop trading infrastructure and publish independent working papers on execution, position sizing, and result measurement. The research distinguishes recorded outcomes from simulations and makes its assumptions and limitations available for review.

I’m open to software engineering, technical sales, and research collaborations. My resume is available above. Biography and media resources.

                  Build
                  StopHarbor & Global Ticket Pay
                

                  Research
                  Zimmër Trading
                

                  Code
                  Full-stack engineering
                

                  Texas
                  Based in San Antonio
                

Skills & Technologies

Tools and technologies across the full stack

Frontend

ReactJS

Next.js

HTML5

CSS3

JavaScript

jQuery

Backend & Core

Java

Python

Node.js

DevOps, Tools & Deployment

Git

GitHub

Cloudflare

Vercel

Visual Studio

Featured Projects

Platforms built for real-world impact

Flagship Live

Global Ticket Pay (GTP)

Traffic-citation lookup and payment service operated by GTP Systems Inc. Drivers can search supported public court records in Texas, Georgia, and Alabama, then choose payment assistance for eligible citations. My work spans the lookup infrastructure, customer workflow, and payment integrations.

Sub-Platform GTP Internal Business Directory (IBD)

React Next.js TypeScript Python SQL Playwright Supabase Cloudflare Vercel

Visit Platform

Live

StopHarbor

Route planning for small field teams. Bring addresses into one workspace, divide stops across workers, review daily itineraries, and hand each worker a private route link. Built around the office-to-field handoff.

React Supabase Geoapify Stripe

View Project

Live execution Read-only overview

Zimmër Trading

Independent quantitative research and trading infrastructure for prediction markets. Explore working papers on execution, position sizing, and result measurement, alongside a dated public snapshot of recorded trading activity.

Python TypeScript SQL Kalshi

Explore Zimmër Trading

View All Projects

Writing

Essays, research, and ideas I’m working through.

Zimmër Trading · Working Paper 03 · November 2, 2026

The Price of a Winning Streak

A live-trading case study of early profits, changing position size, and a reversal across 46 completed markets. Includes data and reproducible calculations.

Read the paper

View All Writing