LEO YONG
DALLAS, TX — : — — SLATE

leo yong

It's beauty in the struggle, ugliness in the success.

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Work

01 UrbanKit Studio — civic tools → 02 More on GitHub →

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soundcloud.com/leoyrh

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32.7767° N
96.7970° W
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Leo Yong

Full-Stack Software Engineer · Dallas–Fort Worth, TX

ryong1@uco.edu · leoyrh.com · linkedin.com/in/leoyrh

Full-stack software engineer with 6+ years shipping production web apps and platforms, from SQL Server schemas through C# and .NET APIs to Angular and React front ends. Modernizes legacy systems, hardens integrations, and protects sensitive data, from HIPAA e-signature software to a credit portal that encrypts SSNs and bank numbers. Builds daily with agentic AI tooling, including a personal multi-agent engine built on Claude Code and Codex.

Experience

Applications Developer

The Arnold Companies (TAC) · Dallas, TX · Apr 2024 – Present

  • Took an AI-built prototype to production as an in-house credit portal that replaced a SaaS product, live since Sep 2026. Moved it on-prem within 2 days of the decision to self-host, with Entra ID SSO and AES-256-GCM encryption of SSNs.
  • Made every outbound automation feed verify delivery in 27 changesets over 10 weeks: stopped about 500 lost price quotes (134 of 283 customers on the fuel industry's document network) and the outage pattern behind 685 duplicate invoices.
  • Proved a vendor's quote engine drops documents silently and built a self-healing guardian: a lost price book's worst case fell from 16 hours to about 1, unattended; 99.78% of 3,605 simulated losses rebuilt byte-perfect.
  • Found 245 invoices worth $4.7M (47 accounts) that never reached customers, closed the file race behind it, and gave Accounts Receivable the resend list.
  • Led the Sybase to SQL Server migration of a 24/7 VB.NET platform serving 200+ employees, rewriting 8 jobs and 10 stored procedures; its main sync, rebuilt on the new database, went from 2+ hours to under 5 minutes (95%+ faster).
  • Tuned a vendor-owned SQL Server with 12 additive indexes and 2 procedure edits, each approved and revertible: 66.5% fewer reads on the 3 heaviest quoting procedures (725M to 242.7M) and 69% less freight-rating CPU.
  • Shipped 7+ production .NET Web APIs, the Angular Central Services hub, a React sales app used weekly by 20+ account managers, and Mailroom, a Microsoft Graph document gateway in production 3 weeks after handoff (shadow mode).

Software Engineer

QuikTrip · Tulsa, OK (Hybrid) · Nov 2022 – Jan 2024

  • Built and maintained .NET web, WPF desktop, and console apps rolled out to 1000+ stores and corporate at a 100% rollout rate, on Azure DevOps and Git CI/CD in Agile sprints.
  • Covered biweekly IT support rotations in Cherwell, resolving cash store audits, data inaccuracies, and connectivity issues under tight SLAs.

Azure Support Engineer III — PaaS Developer Pod

Microsoft · Irving, TX (Remote) · Sep 2021 – Nov 2022

  • Held a 99.9% SLA in the Azure Service Bus domain for clients across North America, APAC, and EMEA, de-escalating tense situations and sharpening ticket scoping.
  • Diagnosed complex Azure Service Bus and Messaging issues with Kusto log analysis, Wireshark and Fiddler captures, and C#, Java, and Python debugging across AMQP, Kafka, and HTTP.
  • Drove cases forward in daily triage and helped teammates with theirs, refining resolution strategies with Technical Advisors and Principal Technical Advisors.

Full-Stack .NET Developer

Center for Advanced Public Safety, University of Alabama · Tuscaloosa, AL (Remote) · Jun 2021 – Sep 2021

  • Delivered front-end and back-end features across the full SDLC in an Agile team on .NET transportation systems for the State of Alabama and the federal NMVTIS program.

Software Engineer

AIC Title Service / Med Claims Services · Oklahoma City, OK · Jul 2020 – May 2021

  • Sole developer of Sapphire Sign, a full-stack Angular and ASP.NET Core app for HIPAA-compliant document generation and e-signatures, used daily by 100+ clinicians and integrated with PICIS and the Oklahoma Department of Health.
  • Rewrote and redesigned Sapphire Connect from the ground up in VB.NET, SQL, JavaScript, and jQuery, improving performance and user experience.

IT Service Desk Specialist & CS Student Assistant

University of Central Oklahoma · Edmond, OK · 2017 – 2020

  • Supported 16,000+ faculty, staff, and students, handling 150+ daily interactions and resolving 20+ tickets a day (VPN, Banner, networking, email, access) in TeamDynamix.
  • As a CS research assistant, built LeolexaPi, IoT home automation on Raspberry Pi with Alexa, AWS Lambda, and the Alexa Skills Kit, and explored OpenCV facial recognition and a GCP Dialogflow Flutter chatbot.

Technical Skills

Languages
C#, TypeScript, JavaScript, Python, Java, T-SQL, PowerShell, HTML, CSS, XAML, VB.NET
Frontend
Angular, React, Vite, Nx, Module Federation, micro-frontends, WPF, jQuery, Bootstrap
Backend
.NET 8/9/10, .NET Core, ASP.NET Core Web APIs, Entity Framework Core, LINQ, Quartz.NET, SignalR, Node.js, Express
Databases
SQL Server, T-SQL, SSMS, SSIS, DACPAC, Query Store, Extended Events, PostgreSQL, Sybase, Elasticsearch, Kibana
Cloud & DevOps
Azure, Azure DevOps CI/CD, TeamCity, OctoDeploy, Git, IIS, Windows Services, PowerShell, Ubuntu, Cloudflare, Vercel, Supabase, Stripe, Visual Studio, VS Code
APIs & Auth
Kong API Gateway, Microsoft Graph, REST, JWT, ACL, CORS, Active Directory, Entra ID, RBAC, OAuth
Architecture
CQRS, REST, SignalR, microservices, module federation
AI & Agentic Tooling
Claude & Claude Code, ChatGPT & Codex, multi-agent orchestration, custom subagents, skills & lifecycle hooks, MCP servers (TypeScript, JSON-RPC), agent evals, prompt & context engineering
Practices
Agile, Scrum, TDD, SOLID, OOP, Clean Code, unit testing (xUnit)

Selected Projects

UrbanKit Studio — Founder & AI Engineer

urbankitstudio.com · Remote · Jan 2026 – Present

  • Built and run a parcel data platform covering 483 US counties in all 50 states and DC, serving people through free browser tools and AI agents through a hosted MCP server with 10 tools.
  • Publish an open-source MCP server, TypeScript SDK, and CLI on npm under MIT, and sell a metered REST API on Stripe. 8,000+ tests gate every deploy.

CAE Harness — Autonomous Claude Code Engine

Personal project · Versioned agentic development system · 2025 – Present

  • Built a versioned engine (v56) that turns Claude Code into a safe autonomous development system: 23 subagents, 37 skills, and 34 lifecycle hooks, with semantic memory search and an Obsidian knowledge base.
  • Claude and Codex review risky changes before merge, new checks get proven by breaking the code on purpose, and two parallel lead sessions split work through resource claims and worktree-isolated subagents.

NACA — Neural Autonomous Core Architecture

Personal project · Node.js and Ink/React terminal app · 2026 – Present

  • Built a private conductor that runs Claude Code and Codex on my own subscriptions and fails over to Codex at task boundaries when Claude is capped, with a persistent task queue, Discord control from my phone, and redacted audit logs.

Education & Certifications

B.Sc. in Computer Science — ABET-Accredited

University of Central Oklahoma, Edmond, OK · 2016 – 2020

Magna Cum Laude, 3.8+ GPA. Honors: Computer Science Outstanding Graduate Award, President's & Dean's Honor Roll. Certifications: Microsoft Certified Azure Fundamentals; Vibe Coding, Gold Tier (Lovable); Front-End & Flutter Development (LinkedIn Learning).

Leo Yong · Dallas–Fort Worth, TX GitHub · LinkedIn · Email
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