Hi, my name is
Joseph Bermudez.
I build software 100+ dealerships rely on.
At Relativistic Engine, I built and own the accounting platform inside our automotive software, where every deal must balance. I also founded VendorX, an online ordering company for distributors and wholesalers. I designed and built its software, directing AI coding agents held to my plans and the checks I set. Our first customer has signed and goes live in early 2027.
About Me
I got into programming in the summer of 2013, after I met someone who showed me how code could turn a simple idea into a working product. I've been writing software ever since. The tools keep changing, but I still like watching people get their work done with something I built.
I started VendorX in 2024 to give distributors and wholesalers a simpler way to sell online. In this industry, most orders still come in by phone, fax, or email. A custom ordering system can cost a distributor hundreds of thousands of dollars and take more than a year to build. VendorX is made mainly for electrical distributors, and it works for brands in other industries too.
I'm at my best when I can see a feature all the way through, including the database underneath it and the screen a customer sees. Owning the accounting platform at Relativistic Engine, where a refund has to match the books to the penny, has taught me to care about the details a business can't afford to get wrong and to test my work carefully before anyone relies on it.
Here are a few technologies I've been working with recently:
- C# / .NET 10
- React 19
- TypeScript
- Next.js 16
- PostgreSQL
- Vue 3
- Elasticsearch
- BigQuery
Where I've Worked
Software Engineer @ Relativistic Engine
April 2022 to Present
- Built and own the accounting platform that turns car sales and leases at 100+ dealerships into balanced entries in their official books, from its first prototype in 2023 to today.
- Led the move of the company's dealership software to Vue 3 and TypeScript, wrote custom automated rules that enforce how its code is structured, and upgraded its desktop app to .NET 8.
- Redesigned the refund math after real data showed 18.65% of cancellations late in a warranty contract were stuck because the refund didn't match the books. Cut that to zero, verified across 1,000,000+ simulated cases.
- Replaced hand-matching of vendor statements with a tool that reads PDFs and spreadsheets, matches hundreds of rows to the right deals and records the entries in one click. It now saves accountants hours every week.
- Stopped sales from being booked twice when a transfer to the dealerships' books fails partway and the receiving system cannot be asked what arrived. The deal now stays locked until an accountant signs off.
- Cut the deals page's start-up time from over 3 seconds to under 10 milliseconds, ended freezes on large deals, and made switching dealerships in the accounting screens take about 70% less time.
- Built the rules engine that decides how each deal is recorded. A rule change updates pending entries in one save instead of row by row, and repairs to live data run as a preview first.
- Moved permission checks to the server, so staff see only their approved dealerships and locked accounts lose access within seconds. Built a View As mode that lets testers act as any employee without messaging real customers.
How I Direct AI Agents
Every day at Relativistic Engine, I put AI coding agents to work, and I do the same on VendorX. The agents add speed, but the engineering stays with me: I design the system, set the rules they follow, check what they produce and answer for the result. This is what people now call agentic engineering.
- I plan a feature before an agent writes its code: what it must do, how it fits the system and how I'll know it works.
- I write the rules the code must follow, from coding standards to automated checks that block changes that break the system's structure or let the screens and server fall out of step.
- I built custom tools and reusable instructions that teach the agents how my project works, so they follow the patterns I set instead of guessing.
- Nothing ships on an agent's word. I read every change before it merges, and it must pass the automated tests and checks I require. On VendorX, some of them check that one business cannot see another's data.
I also decide where AI stops. In my plan for a leadership briefing, AI writes only the wording and never sees numbers or customer data. Code fills in every figure, and 12 checks screen each draft.
- xUnit
- Vitest
- Playwright
- ESLint
- GitHub Actions
- Claude Code
- MCP servers
- Agent skills
Projects I Keep Up With
Artificial Intelligence
ChatGPT
ChatGPT made AI feel personal. Instead of a clunky chatbot, you get a conversation that actually understands what you're asking. It can write code, draft an email, or walk you through a hard topic in plain language.
- Natural Language Processing
- Large Language Models
- Reinforcement Learning from Human Feedback
Space Exploration
Starship
Starship is SpaceX's bet on making humanity multi-planetary, and it's the largest and most powerful rocket ever built. It's also designed to be fully reusable. SpaceX has already caught the returning booster with the launch tower's mechanical arms, which I still find hard to believe.
- Rocket Propulsion
- Avionics
- C++
- Python
Digital Currency
Bitcoin
Bitcoin started as a whitepaper and became the world's first decentralized currency, letting people send value to each other over the internet without a bank in the middle. It runs on a global network of computers, secured by proof-of-work mining, and no single party controls it. Whatever you think of it, it launched an entire industry and changed how we think about money.
- C++
- SHA-256 Proof-of-Work
- Lightning Network
- Peer-to-Peer Networking
Automation
Full Self-Driving (FSD)
Tesla's FSD is teaching cars to drive themselves by reading the road and making decisions in real time, instead of following pre-mapped routes. Driving data from the fleet feeds back into the neural network, so the system keeps getting better. It's one of the hardest problems in engineering, and I find it fascinating to follow.
- Neural Networks
- Computer Vision
- C++
- Python
My Projects
VendorX
Online ordering software for distributors and wholesalers, mainly in electrical supply and open to other industries. Each business gets its own branded store where customers can request quotes and order any time instead of calling, faxing, or emailing. Pricing, payments, accounting, and shipping are handled in one place. Our first customer, a distributor, goes live in early 2027.
Contact
Get In Touch
I'm always glad to hear from people. If you have a project in mind or a question about VendorX, send me a note and I'll get back to you.