rljayl

Senior Full-Stack Engineer / Data and Database Engineer with 15+ years of experience designing, deploying and maintaining web applications, database architectures and server infrastructure. Lead Architect for a major national search directory designing database and application architectures from the ground up, including schema design, stored procedures, search logic, data migration and infrastructure.

Interested in data-driven software engineering and emerging technology projects where practical engineering can contribute to meaningful scientific, technological or societal outcomes, innovative, creative products or improve existing systems saving people time. 

Recent work: Node.js/EJS/Express Web Development, MySQL, SQL Server, JSON, Linux/Bash/Node.js automation for data export and imports, Node.js JSON RESTful API. Ranked 7th place among 150+ participants in a 2025 Cyfrin CodeHawks First Flights smart contract security smart contract audit competition.


Education 

BSc Computer Science (University of Cape Town) 

Skills and Core Competencies 

Core Programming Languages

Languages: JavaScript ES6+ (Frontend & Node.js), C++, C#, SQL, Java (Server-side & Processing), Solidity, Cypher, Python (File IO & Graphing), HTML5/CSS3

Backend Development, Database Design 

• Web Frameworks: Node.js (Express, EJS), C# ASP.NET, RESTful APIs 
• Database Management: MS SQL (SQL Server Management Studio), MySQL, MS Access, Neo4j (AuraDB), Stored Procedures, Performance-Orientated Design (with Indexes) and Constraints 

Blockchain & Web3 

• Smart Contract Engineering (Polygon, Ethereum): Developing custom, secure Solidity contracts (including ERC-20, ERC-721), across Ethereum and Polygon networks, with payable functions, funds routing, and events, using Remix and Foundry 
• Mainnet Deployment: Deploying live contracts on Polygon and Ethereum mainnets via Remix and Foundry, Smart Contract Verification on Polygonscan, interacting with live contracts via block explorers (Polygonscan / Etherscan) 
• Oracles & Data Feeds: Integrating Chainlink Oracles into custom smart contracts to pull real-time, real world data (including live currency exchange rates) 
• Full-Stack Web3 Integration: Building dApps that interact with the blockchain, to read/write on-chain data (Ethers.js and RPC URLs) trigger automated funds transfers, and update web front-ends in real time 
• Testing & Interaction: Executing smart contract functions and automated testing suites via Foundry CLI, utilizing specialized state testing functions to simulate complex user flows, time-locked events, and multi-user interactions,  alongside front-end integration testing via Remix and Website front ends 

Data Science, Analytics, Visual Dashboards and Reports 

• Graph Databases: Neo4j Ecosystem (AuraDB, Aura Console, Aura Bloom). Schema Design, Data Modelling 
• Data Visualizations: Interactive Web Dashboards (HTML/CSS) querying Database, 2D Web Animations(JavaScript Canvas), Web Basic 3D (P5.js), Python Data Graphing, Database/JSON visualizations, SVG programming, Graphical Report Generation (HTML/CSS), Physics Simulations with Numerical Methods in 3D (Processing, JavaScript) 
• Data Science, GIS & Simulations: NASA Geospatial Data Processing (EMIT hyperspectral, UAVSAR), Machine Learning via TensorFlow (Node.js), Advanced SQL queries, JSON Processing, Excel (Graphing & Analytics), Neo4j (Graph Creation, graph based queries, export to CSV)

Hardware, IoT and Embedded Systems 

• Hardware & Engineering: Microprocessor Programming (Arduino/C++), Basic Circuit & Breadboard Design, IoT Telemetry 
• Sensors & Robotics:Environmental Sensors (CO2, TVOC, Temp/Light), Acceleration & Orientation (Accelerometers), Robotics & Motor Control (Servos, Rover Chassis), Speaker (Tone based), Lights (LEDs / Addressable LED strips)

DevOps, Server Administration & Cybersecurity 

• Infrastructure & Servers: Linux/Ubuntu Server, Windows Server, Hostinger (hPanel / CloudPanel), SQL Server Management Studio (SSMS), PM2 Production Process Management 
• Cybersecurity & Hardening: SQL Injection Defence, User Input & Upload Validation, Network Firewalls (Subnet-level rules, DB and CloudPanel Port Restrictions), DDoS Awareness, Phishing Awareness 
• Network, Email and Domain Level Admin: SSH Remote Administration (Linux), SSL/TLS Certificate Setup, DNS & Subdomain Routing, Email Authentication (DMARC, SPF, DKIM), SSH Port forwarding  (MySQL & CloudPanel) 
• Scripting & Automation: Automated PDF Generation, Programmatic Email Dispatch, System Scripts (Bash, PowerShell), Custom Linux Server Tools (C++/Java/Node.js)