Eric Russel M. LopezFull-Stack Developer · Systems Architect

I build software systems — data models, APIs, backend logic — for businesses that need things to actually work.

I've been building database-driven applications since 2020 — mostly for companies in logistics, real estate, healthcare, and finance. I care about normalized schemas, secure APIs, and deployments that don't fall over.

View Work Download CV Get in Touch

Experience across

Real Estate
Logistics
Healthcare
Finance

Focus Areas

System Architecture
Relational Database Design
API Development
Deployment & Hosting

Rusbyte Initiative

Founder of Rusbyte — independent studio building client software from schema to deployment.

About

What I do and how I got here.

I'm a full-stack developer and the founder of Rusbyte. Since 2020, I've been building web applications and relational databases for companies in logistics, real estate, healthcare, and finance — mostly multi-tenant systems with role-based access, reporting dashboards, and the backend plumbing that holds it all together.

I focus on system design and writing code that's easy to maintain long-term. Most recently, I built the database layer and RBAC system for Oakford Realty, an Australian real estate company. I care that every API endpoint and database table actually serves a business need — not just a technical one.

Outside of web development, I've built microcontroller-based robotics and IoT projects — one of which won an award for fire-rescue automation. I also led web dev workshops as the Assistant Lead for Google Developer Groups on Campus, mentoring students on JavaScript, React, and writing clean code.

Maintainable Architecture

I write clean code, document it properly, and structure projects so the next developer (or future me) can pick it up without guessing.

Server-Side Boundaries

I enforce RBAC and row-level isolation on the server. If a user shouldn't see it, the API shouldn't return it — simple as that.

Performance as a Requirement

Slow software loses users. I optimize queries, reduce payload sizes, and test for accessibility because speed and usability aren't afterthoughts.

Experience

Where I've built and led.

Professional work and leadership, focused on shipping real software and raising the bar for the people around me.

Founder & Full-Stack Developer
Work
Rusbyte — Independent Software Development Studio · Present
I started Rusbyte as an independent software studio. I build web apps, mobile tools, and database backends — working directly with clients to turn their workflows into production-ready software. The focus is always on normalized schemas, secure APIs, and deployments that hold up.
- Design database schemas, write REST APIs, and build frontends end-to-end.
- Set up RBAC and build custom reporting tools matched to how each client actually operates.
- Work directly with clients — translate their business rules into schema designs and software.
- Own the full deployment pipeline: CI/CD, hosting, environment configs.
Full-Stack Developer
Work
Oakford Realty · Real estate company operating in Australia · Feb 2026 – Mar 2026
I built full-stack features for an Australian real estate agency — property listings, client records, and internal tools for daily operations.
- Designed the relational database layer for property records and transaction logging.
- Built backend API endpoints and dashboard components for daily admin workflows.
- Implemented user auth and RBAC to lock down access properly.
- Built reporting views that consolidated multi-agent property tracking into one place.
- Found and fixed performance bottlenecks in database queries and code structure.
Web Development Assistant Lead
Leadership
Google Developer Groups on Campus · Academic Year 2024–2025
Selected as Web Assistant Lead on campus. I organized and taught web development workshops, helping students go from beginner concepts to building actual projects.
- Mentored students on HTML/CSS, JavaScript, and React through code reviews and live build sessions.
- Helped organize community events and bootcamps for the developer community on campus.
- Wrote the workshop curriculum and led live coding demonstrations.
- Earned a Certificate of Completion from GDG on Campus.

Technical Validation

Certifications and technical credentials.

Industry certifications that back up what I've built in production.

Certification

Information Technology Specialist (ITS) — Databases

Certiport / Pearson VUE

Covers relational database design, query writing, and data administration. I use these fundamentals daily — normalizing schemas, writing SQL, and optimizing data structures in production.

June 2026

Certificate

Web Development Assistant Lead — Certificate of Completion

Google Developer Groups on Campus

Received for leading web dev bootcamps on campus. I wrote the syllabus, ran live workshops on JavaScript and React, and mentored students through code reviews.

AY 2024–2025

Associate

Microsoft Office Specialist (MOS) — Word 2019 Associate

Microsoft / Certiport

Covers advanced document layout and automation. In practice, I use it for writing technical specs, database documentation, and API docs.

May 2024

Skills

The stack I build with.

What I use day-to-day to design, build, and ship software.

Frontend

Responsive, accessible interfaces that work well across devices and are easy to maintain.

React
Next.js
TypeScript
JavaScript
Tailwind CSS
HTML5
CSS3
Responsive Design

Mobile App Dev

Cross-platform and native mobile apps — performant rendering, offline support, and device integration.

Flutter
React Native
Kotlin

Desktop Applications

Desktop apps and GUIs with event-driven architecture and native system integration.

Python
PyQt
PySide
Tkinter
Java
JavaFX
Swing

Backend

APIs, auth systems, business logic, and backend services for real-world workflows.

Node.js
Java
Python
REST APIs
Authentication
Role-Based Access Control
PHP
Server Actions

Databases

Schema design, query optimization, and data integrity — built to last.

SQL
MySQL
Firebase
Database Design
Query Optimization

Cloud & Deployment

Deployments, environment management, and keeping production stable.

Vercel
Railway
Git
GitHub
CI/CD
Environment Management

Tools

The tools and workflows I rely on every day.

VS Code
Git
npm
Claude
ChatGPT
Copilot
Gemini

Practices

The practices I follow to keep code clean and projects on track.

Clean Architecture
SEO
Performance Optimization
Code Review

Solutions

Systems I've built for real businesses.

Web applications and backend systems built for real estate, logistics, healthcare, and finance — each one designed around the client's actual workflow.

Flagship Product2025

Lojaroute

Multi-tenant logistics platform with automated dispatch, live fleet tracking, and driver cash reconciliation.

React 19
Node.js
Express.js
React Native
MySQL
Ably Realtime

Read the case study

Client Project2026

Real Lux

B2B wellness and lead-generation platform featuring dynamic ROI calculators and interactive spatial layout tools.

React
TypeScript
Vite
Framer Motion
Tailwind CSS
HTML5 / CSS3

Read the case study

Real Estate

Real Estate Operations Systems

Problem: Agencies dealing with transaction delays and data exposure from fragmented listings, undocumented agent assignments, and unsecured client records.
Solution: A centralized platform for managing property listings, agent permissions, and client transaction histories.

Key features

Normalized schema design for unified property registries and customer history tracking
Server-side role-based access control (RBAC) protecting sensitive agency contracts
Administrative dashboard monitoring listing status changes and agent workflow queues
Strict event auditing and session security for client document modifications

Next.js
TypeScript
Node.js
MySQL
Tailwind CSS
RBAC

Impact

Normalized the database to maintain referential integrity, cut query times, and established a full audit trail for all administrative actions.

Logistics

Logistics Fleet Platforms

Problem: Fleet operators experience vehicle bottlenecks and delivery verification disputes when relying on manual routing and offline coordination.
Solution: A multi-tenant dispatch system with live GPS tracking, automated routing, and verified driver handoffs.

Key features

Low-latency fleet telemetry synchronization and vehicle tracking
Route rendering and sequential driver dispatch management
Automated background workers processing vehicle status updates and billing actions
Segmented client dashboards for branch managers, drivers, and cargo clients

Next.js
TypeScript
Node.js
PostgreSQL
Tailwind CSS

Impact

Built a high-throughput GPS pipeline with database-level tenant isolation — reduced dispatch overhead and eliminated delivery disputes.

Healthcare

Clinical Records Systems

Problem: Private practices stuck on paper charts and fragmented scheduling, risking compliance issues and double-bookings.
Solution: A HIPAA-aligned system for digitizing health records, physician scheduling, and patient billing.

Key features

Encrypted database columns for patient health histories and physician consultation logs
Concurrency-checked scheduling logic to prevent double-booking of doctors
Automated billing structures generating transactional records and receipts
Strict database policies restricting patient record queries to authorized clinical staff

Next.js
TypeScript
Node.js
MySQL
Tailwind CSS
RBAC

Impact

Added database-level encryption and strict access rules to secure patient data. Eliminated scheduling conflicts.

Finance

Transactional Ledger Systems

Problem: Collateral lending requires strict audit trails, precise asset valuation, and automated compliance reporting to pass regulatory reviews.
Solution: Ledger management and inventory system tracking collateral assets, calculating loan interests, and auditing daily transactions.

Key features

Barcode-mapped inventory tracking for collateral appraisal and vault storage
Double-entry transaction ledger auditing loan releases, interest accruals, and redemptions
KYC-compliant customer registry holding credit history logs
Automated end-of-day balance sheet reconciliation and audit trail export tools

Next.js
TypeScript
Node.js
MySQL
Tailwind CSS

Impact

Built double-entry database schemas that maintain transaction accuracy and automate regulatory reporting.

Embedded Systems & IoT

Software meets hardware.

Microcontroller projects, sensor integrations, and hardware builds for safety and monitoring.

Outstanding Investigatory Project

Fire Rescue Robot

An autonomous robot that navigates hazardous zones and locates fires. I wired the circuits, designed the power routing, and wrote the microcontroller code to read flame and ultrasonic sensors in real-time.

Microcontroller programming and event-driven sensor polling loops
Integration of flame sensors and ultrasonic transducers for navigation
Control logic for autonomous heat source localization and safety systems
Custom circuit design, hardware prototyping, and power supply routing

Embedded Systems
Sensors
Automation
Robotics

Food Spoilage Detector

An IoT monitoring station that detects food spoilage early by tracking storage conditions. Built with an Arduino Uno, MQ-4 gas sensor, and atmospheric sensors — triggers LCD alerts when readings go out of range.

Arduino hardware integration with MQ-4 gas telemetry and DHT sensors
Low-latency polling of atmospheric methane levels and ambient temperature
Local alert logic using physical indicators and LCD status displays
Applying embedded engineering to automate storage condition audits

Arduino Uno
MQ-4 Gas Sensor
IoT
Atmospheric Monitoring

Initiative

Founder & Full-Stack Developer

Rusbyte — Independent Software Development Studio

I started Rusbyte to build software the way I think it should be built — directly with clients, from database schema to deployment. We build web applications, mobile tools, and backend systems, with a focus on getting the architecture right from day one.

Software Discipline

Every project gets production-grade treatment: clean code, documented architecture, and secure deployments.

Full-Stack Delivery

Building from the database layer up to the UI, making sure the backend and frontend actually talk to each other properly.

Iterative Development

Ship fast, test under real conditions, and refine until it's solid.

Read the Rusbyte case study Visit Studio Site

Contact

Let's work together.

Open to full-time roles, freelance projects, and collaborations. Drop a message or reach out below.

ericrussellopez@gmail.com

GitHub

See the code