Lucas Spain
Software engineer specializing in generative AI
I build web applications and AI agent systems: retrieval pipelines, LangGraph graphs, and the interfaces in front of them. Four years shipping at John Deere, from the React frontend down to the AWS bill.
About
I'm a software engineer who moved from full-stack web development into AI. I've worked across the whole stack, from infrastructure and pipelines to the interfaces people use.
I started at John Deere in the Information Technology Development Program, where I worked on full-stack applications, CI/CD pipelines, and AWS infrastructure. That work in deployment and site reliability still informs how I build today.
Now I focus on AI applications: retrieval systems and agent workflows with LangChain, LangGraph, and the OpenAI APIs.
Career journey
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Graduate Teaching Assistant
Supported students at University of Iowa in understanding programming and logical concepts.
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ITDP
Joined John Deere, developing full stack applications using React and Spring, hosted on AWS. Focused on site reliability engineering, CI/CD pipeline development, and cloud infrastructure management.
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Software Engineer
Built a full-stack web application with a React frontend and a Spring Boot backend.
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Senior Software Engineer, AI Solutions Team
Building AI applications with LangGraph, LangChain, the OpenAI APIs, and RAG.
- Bettendorf, Iowa
- 4+ years professional
- M.C.S., University of Iowa
- Code-pair & behavioral interviewer
What I do
AI Applications
Production agents and RAG systems built with LangGraph, LangChain, and the OpenAI APIs.
Full-Stack Development
React and Spring front-to-back, with FastAPI services and PostgreSQL behind them.
Cloud & DevOps
CI/CD pipelines, infrastructure as code, and AWS: Lambda, IAM, and Secrets Manager.
Site Reliability
Built a first-in-org CI/CD pipeline that cut deployment time from a day to 20 minutes.
Teaching & Mentoring
Two years as a graduate TA at Iowa; now a code-pair and behavioral interviewer.
Security
Shipped org-wide CSRF protection and kept zero exploitable vulnerabilities in production.
Skills & tools
AI & Machine Learning
Building AI-powered applications, agents, and retrieval systems.
LangChain · LangGraph · LangServe · LangSmith · OpenAI API · Anthropic Claude · RAG systems · embeddings · vector search · Qdrant · OpenSearch · semantic search · document retrieval · cross-encoders · re-ranking · AI agents · agentic frameworks · MCP · FastMCP · A2A · tool calling · structured outputs · prompt engineering · streaming responses · Whisper · speech-to-text · Ollama · local LLMs · Hugging Face
Frontend Development
Responsive, accessible, and interactive user interfaces.
JavaScript · TypeScript · React · Svelte · SvelteKit · Redux · HTML5 · CSS3 · TailwindCSS · Mantine · daisyUI · Vite · responsive design · web accessibility · single-page apps · server-side rendering · progressive web apps · REST integration · WebSockets · Vitest · Playwright
Backend Development
Server-side applications, APIs, and data layers.
Python · FastAPI · Pydantic · Java · Spring · Spring Boot · Node.js · Express · RESTful APIs · API design · API gateways · microservices · PostgreSQL · SQL · Supabase · message queues · WebSockets · authentication · Rust · C · Haskell
DevOps & Cloud
Infrastructure, deployment pipelines, and reliability on AWS.
AWS · AWS Lambda · Amazon S3 · CloudFront · Route 53 · IAM · CloudWatch · Secrets Manager · Amazon SES · Docker · Terraform · infrastructure as code · GitHub Actions · CI/CD · self-hosted runners · serverless · webhooks · Linux · Bash · Nginx · site reliability (SRE) · monitoring & logging
Tools & Practices
How I build, ship, and collaborate day to day.
Git · GitHub · GitHub API · VS Code · npm · pnpm · Agile / Scrum · code review · conventional commits · semantic-release · unit testing · integration testing · test-driven development · secure coding · debugging · Jira
Project index
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Pride in Motion
The official site for Pride in Motion, the Quad Cities LGBTQIA+ recreational sports league (~200 visitors/week). A full-stack app with event listings, schedules, standings, online registration, and a gated admin CMS, backed by Supabase and served from AWS S3 and CloudFront.
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Gatsby: Local Voice Assistant
A fully local voice assistant using LangGraph and Ollama for inference, with a Whisper-based speech engine over the Wyoming protocol for home automation.
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Personal Website
This site, built with SvelteKit and TailwindCSS. I used agentic coding tools to help put it together.
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Wedding Website
A personalized wedding site designed to double as a template for future events. Built with React and Express, with end-to-end RSVP, guest, request, and gift management.
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Scarf Pattern Generator
A Python desktop app, built before the generative-AI era, that produces scarf patterns with images and printable instructions. It supports symmetric or asymmetric patterns, up to three colors, with adjustable ratios.
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Wyoming Whisper: Multi-User Voice Recognition
A reusable Docker container forked from an existing transcriber for a local voice assistant. It adds speaker labeling by matching voices against embeddings stored locally.
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Plex Uploader
A web app for uploading media to a Plex server. Built with Express and React, it queues files for local AI upscaling before adding them to a Plex library in higher definition.
From My Day Job
Joe, the AI Avatar
An AI avatar kiosk that pairs a HeyGen avatar with a live salesperson over WebRTC and A2A for a resilient customer experience. Added MCP app integration for rich UIs in AI chat, built the chat voice and audio pipeline, and modernized the enterprise site to React 18 with React Testing Library.
Dealer Assistant
An AI chatbot that helps John Deere dealers find answers fast, using retrieval over dealer-facing content to ground its responses.
MCP App Integration
Integrated Model Context Protocol (MCP) apps into AI chat so tools can render rich, interactive UIs inline instead of plain text responses.
CSRF Protection
Designed and rolled out an application-wide change to close an identified security flaw in a production system.
Automated CI/CD Pipeline
Independently built and deployed a first-in-org CI/CD pipeline that fully tested and deployed changes to production, cutting deployment time from a day to 20 minutes.
Francois, the GitHub Bot
Francois, a GitHub bot that automates issue triage and pull-request reviews, wired into GitHub Actions and hosted on AWS Lambda.
Completions API
Designed an internal API for AI use cases that deliberately excludes chat history while encapsulating configuration and exposing tools and structured output.
Experience
Senior Software Engineer, AI Solutions Team
Building AI applications: coding agents, data-processing graphs, and deployed models across AI/ML frameworks and cloud services.
- Developed applications integrating AI agents to assist with coding tasks.
- Built complex LangGraph graphs for data processing and analysis.
- Integrated OpenAI APIs and RAG techniques for better retrieval and responses.
- Used embeddings and OpenSearch for efficient document retrieval.
- Worked with specialized models, including Whisper for speech recognition.
- Built frontend interfaces, managing data streams from React applications.
- Used PostgreSQL for checkpointing and AWS for secrets, Lambda, and logging.
Software Engineer
Built a full-stack web application with a React frontend and a Spring Boot backend.
- Built React frontend features backed by a Spring Boot REST API.
- Delivered full-stack features end to end, from UI to data layer.
- Collaborated on a shared codebase using code review and CI/CD.
Information Technology Development Program (ITDP)
Developed full-stack applications, managed cloud infrastructure, and owned site reliability, delivering features through secure coding, CI/CD, and infrastructure work.
- Kept applications reliable through quality checks and infrastructure tuning (SRE).
- Designed CI/CD pipelines using GitHub Actions and AWS.
- Maintained zero exploitable application vulnerabilities through secure coding.
- Shipped both frontend and backend features end to end.
- Maintained scalable, cost-aware AWS infrastructure.
Graduate Teaching Assistant
Supported undergraduates in programming and logic by leading lab sections and giving feedback on their work.
- Led lab sections to help students grasp programming and logical concepts.
- Reviewed assignments and projects to give feedback that supported student growth.
Get in touch
Direct channels
Education
The University of Iowa
Master of Computer Science