Embedded systems · PCB design · Automation
Roger Mendoza — a technical product and systems engineer who started in avionics, spent 20+ years in networks, enterprise architecture and automation, and now designs ESP32 boards, firmware and 3D-printed hardware from first sketch to working prototype.
A dedicated, fully offline speedcubing appliance that sits beside a StackMat and keeps the session — taken from requirements to PCB, firmware, 3D-printed enclosures and working prototypes.
The physical media Reticulum doesn't model, modelled properly: LoRa with an enforced duty cycle, dial-up telephone priced per session, receive-only media — and honest arithmetic for all of them.
A daily scanner of ~3,700 small, mid and micro caps for volatility squeezes and three-week-tight setups, grown into a signals dashboard, content site and automated social pipeline.
An affiliate and SEO management platform that pulls ranking and keyword data, metadata workflows, structured FAQ data and affiliate-link management into one reviewable place.
Three phase-driven coils and a three-axis magnetometer testing a 3/6/9/12 addressing concept — where the biggest result was that nine symbols belong on a sphere, not a dial.
Onboarding, content, sales, chart-analysis and workflow tools built with Python/FastAPI, OpenRouter, Replicate, n8n and MCP-connected services — plus the e-commerce and CRM systems behind 17,000+ customers.
Unusual ideas show up in hardware projects — 3-6-9, vortex maths, golden spirals, "smart money" flow. I give each one an honest test and write down the result, dead ends included. The write-up covers what survived, what didn't, and the corrections I owed along the way.
Take the theorem; test the claim. The mathematics hiding inside those ideas produced the biggest engineering gain in the project.
Read the paperTwo decades of keeping critical systems up — hospitals, insurers, telecom — then building my own products. The through-line: take a fuzzy requirement, make it real, measure it, improve it.
KiCad, ESP32, RP2350 / Pico-class MCUs, schematic capture, PCB layout, board bring-up, GPIO, PWM, serial interfaces, component integration
OpenSCAD, STL workflows, Forge ADX5, 3D printing, enclosures and fixtures, fit/tolerance checks, design-for-assembly
Python, MCP setups, automated routing and consistency checks, firmware test generation, design-review workflows
Claude, ChatGPT, OpenRouter, LiteLLM, CrewAI, Cline, Replicate, agent workflows, structured outputs, prompt engineering
FastAPI, REST APIs, PostgreSQL, SQLite, n8n, Zapier, Docker, Railway, AWS
TCP/IP, routing & switching, VPN, Cisco, Citrix, NetScaler, VMware, disaster recovery
Outside of client work and the bench, I run two community efforts close to home.
A non-profit that runs outdoor camp days for children with unique abilities — ten acres of land with an obstacle course, zipline and tire swings, water play, chickens and ducks, a food forest garden, metal detecting and music, with a behavior (ABA) therapist on site.
A homeschool social group that gives kids a place to learn, be themselves and make friends — building community for homeschooling families in the Wesley Chapel area.
From a dev board on a breadboard to a custom ESP32-S3 PCB — the layout, the manufacturer checks, the firmware architecture that runs on more than one board, and an honest milestone list.
Adding a dial-up telephone carrier to a LoRa mesh exposed a routing bug that no test caught — it would have been discovered as a phone bill.
Two Heltec V3 radios, one evening, and a round-trip time predicted before it was measured. What the first real-RF runs of Dictyon-net taught me about honest arithmetic.
I gave 3-6-9 numerology, vortex mathematics and the Rodin coil one honest test each. Most claims didn't survive — but the mathematics hiding inside them produced the biggest engineering gain in the project.
Hardware, firmware, software and customers all respond to the same loop. A look at how I take an idea from first sketch to working prototype — and why the loop matters more than any tool.
A burst of AI-assisted research produced 88 findings in two days. Auditing them against their own rules found that the filter never ran — and that the audit was the most useful finding of all.
Hardware prototypes, embedded products, automation that people actually adopt, or a second opinion on a board before it goes to fab — the best way to reach me is through Mendoza Solutions.
Get in touch via Mendoza Solutions ↗