
Scotty Waggoner
Verified Expert in Engineering
Software Developer
Sacramento, CA, United States
Toptal member since February 17, 2021
Scotty is an experienced full-stack developer who builds high-performance web and mobile applications with TypeScript, Node.js, Next.js, and React. He specializes in optimizing architectures, enhancing developer experience, and integrating AI-powered solutions. With a passion for problem-solving and user experience, Scotty delivers scalable, intelligent systems that drive real-world impact.
Portfolio
Experience
- React - 9 years
- TypeScript - 9 years
- Node.js - 8 years
- PostgreSQL - 8 years
- React Native - 8 years
- Next.js - 7 years
- Internet of Things (IoT) - 5 years
- OpenAI - 3 years
Preferred Environment
Visual Studio Code (VS Code), Linux, Rust
The most amazing...
...feature I've worked on was Ask AI for FoodNoms, enabling users to instantly access detailed nutrition information from descriptions, images, and recipes.
Work Experience
Fractional CTO
Freelance Startup
- Provided audit and next steps with Lovable AI-generated codebase (priority tasks, GitHub Actions guardrails, schema cleanup).
- Helped figure out the direction of MVP and the hiring of developers.
- Advised on product scoping, design strategy, and oversaw product analytics strategy.
React Native and Back-end Engineer
AirPay
- Built a peer-to-peer payments app end-to-end as the sole engineer: a React Native/Expo client, a Hono back end, a shared crypto package for broadcasting privacy-preserving nearby IDs, and a custom module wrapping Google Nearby for device discovery.
- Architected the back end on Hono and Cloudflare Workers with Neon Postgres and Kysely, giving end-to-end TypeScript type safety from the database schema through to the mobile client.
- Designed a privacy-preserving nearby-discovery protocol using HPKE encryption, so devices broadcast encrypted tokens that only the server can resolve to a user instead of putting the account identity on the air.
- Enforced Postgres row-level security with least-privilege database roles so each request only reaches its own user's accounts and payment data, working correctly under Cloudflare Hyperdrive's connection pooling.
- Diagnosed and patched two native crypto bugs, including one that silently zeroed out the AES key, to get the encryption working consistently across the React Native and Cloudflare Workers runtimes.
- Integrated Coinbase wallets with USDC-on-Base rails and fiat on/off-ramp, chosen after evaluating conventional payment processors and ruling them out on policy and cost grounds for open peer-to-peer transfer.
- Created a custom React Native module wrapping the native Google Nearby iOS and Android libraries for proximity-based device discovery, since no public package existed.
- Engineered forward secrecy into the nearby-discovery protocol using short-lived server keys stored in Cloudflare Workers KV that rotate on a schedule, so expired tokens can no longer be resolved to any user.
Full-stack Developer
Health Plans of North Carolina
- Implemented marketing, quoting, and scheduling website with Next.js, significantly improving SEO, search rankings, performance, and conversions.
- Held a lead engineer position, making critical product and technical determinations, scoping new tasks, overseeing another engineer, and conducting code reviews.
- Handled integrations with the client's CRM, CMS data from Contentful delivered via GraphQL, Calendly for agent scheduling, 3rd-party quoting software, and SMS and email marketing using Next.js serverless API routes and Zapier.
- Created an AI chatbot quote flow using Botpress to help inform and convert users.
Full-stack and AI Developer
Educate to Space
- Built and shipped a production, subscription-gated web app to help parents discover educational resources, including online classes, homeschool curriculum, and local programs.
- Deployed to production in 3 months as a solo dev for a non-technical founder, owning front end, back end, AI, data, and infrastructure end-to-end.
- Architected an agentic RAG pipeline including a router agent, hybrid pgvector search, and OpenAI text-embedding-3-small embeddings that ground LLM recommendations in a curated resource database.
- Built the AI chat interface using Vercel's AI SDK including chat completions, streaming responses, tool calling, and JSON schema validation.
- Eliminated LLM hallucination of fake resources by injecting real database IDs into the structured output schema, forcing the model to return only real, retrievable results.
- Improved retrieval quality with vector search by adding MMR reranking and aggregating per-resource chunk embeddings for diverse, non-redundant, relevant results.
- Built learning-plan curation and per-child organization on a Next.js front-end and Supabase back end using Postgres with RLS, Edge Functions, Supabase Auth, and Cloudflare Turnstile.
- Engineered Stripe subscriptions with subscription-status middleware gating chat, reviews, and Q&A.
- Stood up CI/CD solo with GitHub Actions, deploying migrations and edge functions to production and preview environments with Sentry and Langfuse helping with observability.
- Wired data pipelines feeding the AI: Airtable resource source via webhook (parse, upsert, CRON job for embedding).
Senior Cross-platform Mobile Developer
Stable Analytics, LLC
- Progressed from a requirements document to a fully-working React Native MVP using Expo within two weeks for a successful customer demo.
- Integrated modular Bluetooth connection handling and device communication code to quickly offload payloads from a client's custom microcontroller board.
- Managed states using SQLite and Drizzle to enable data persistence, ease of querying, and combining data from devices and remote sources to power app features.
- Started from scratch without designs and used Figma to prototype ideas and get quick feedback before implementation.
- Implemented UI solutions using NativeWind, a Tailwind CSS implementation for React Native, and Expo router.
Back-end TypeScript Developer
Algebraic Labs, LLC
- Optimized moderation tools, improving DB performance and enhancing accuracy through AI-automated content analysis for user-submitted foods to a crowdsourced database.
- Engineered an AI-powered pipeline for food database matching and nutrient estimation leveraging OpenAI APIs (GPT-3.5, GPT-4, Structured Outputs) and incorporating keyword extraction, dataset filtering, and retrieval-augmented generation (RAG).
- Developed back-end endpoints for an AI-enhanced iOS client app using TypeScript, Deno, Supabase Edge Functions, and PostgreSQL, leveraging custom database functions to optimize query performance for real-time AI interactions.
- Dockerized and deployed a scalable Node.js API and batch processes on Amazon ECS, cutting deployment time and operational overhead while improving reliability and reducing downtime and costs.
- Architected a low-cost pipeline to capture, batch, and store search query metrics for future AI use. Investigated multiple solutions, considered pricing, and architected final implementation involving Amazon Kinesis Data Firehose and S3.
- Developed admin tools and product features with Node.js, Koa, Interval, Knex.js, PostgreSQL, and OpenAI APIs. Iterated on AI prompts and used OpenAI function calling capabilities to structure inputs and outputs.
- Added customizable endpoint rate limiting backed by Redis.
- Enhanced monitoring and logging with Datadog, improving visibility into Amazon ECS, EC2, Nginx, Redis, and Node.js.
- Improved developer experience by setting up VS Code Dev Containers, creating database seeds for testing and local development, and improving TypeScript tooling.
Full-stack Engineer
Chainstarters
- Implemented front-end Web3 integration with Alchemy and Polygon for a client NFT drop site to load NFT data, connect wallets, make smart contract calls, and purchase NFTs.
- Created new GraphQL endpoints and PostgreSQL tables and configured GraphQL Code Generator.
- Used Tailwind CSS, React, and TypeScript to implement marketing sites based on Figma designs.
React Native Developer
Freelance Client
- Implemented a React Native async audio communication app for sales teams, tackling audio recording, playback, transcription, group messaging, and sales goals.
- Designed a GraphQL schema for Apollo Client to be consumed with improved pagination methodologies, cache keys, code generation, and configuration. Refactored screens to fully utilize Apollo's data loading and mutation capabilities.
- Implemented authentication flows using AWS Cognito and social logins (SSO).
Printed Circuit Board Designer
Client (via An Online Freelance Agency)
- Used Autodesk Fusion 360 to create schematics, a PCB layout, a 3D model, and PCB manufacturing files based on a hand-sketched wiring diagram for 18 relays.
- Designed for high currents on specific signals and fitted everything in a small footprint according to the requirements.
- Helped the client through the phases of design and PCB manufacturing and testing.
Full-stack Developer
Cru
- Headed a team updating MPDX, an internal donor management app, using React, Next.js, GraphQL, Material UI, and serverless functions.
- Implemented article recommendation engine API using AWS Lambda to pull batch article recommendation updates from BigQuery, detect changes, and push precomputed JSON files to S3 grouped by page for easy and performant consumption by content sites.
- Oversaw a team implementing MissionHub, a React Native iOS and Android app designed to help grow interpersonal connections using React Native, TypeScript, and GraphQL.
- Led technically on numerous projects by scoping new features, selecting tech stacks, collaborating with stakeholders on requirements, mentoring colleagues, enhancing developer velocity, and addressing product direction choices.
- Created a modern donor user experience on our giving site (give.cru.org). Worked on gift configuration, the checkout process, managing payments, editing recurring donations, and the user's profile.
- Developed an npm library for validating, encrypting, and tokenizing bank account and credit card info. Utilized TypeScript as a wrapper library for our payment processor. Provided a clean API for web apps to consume.
Mobile and Embedded Developer
Freelance
- Created prototype device using an ESP32 microcontroller and small screen to display data in a small form factor.
- Developed a React Native app to control the microcontroller using Bluetooth Low Energy (BLE).
- Implemented UI with Tailwind CSS to send new data to the microcontroller over BLE.
Software Architecture Consultant
Freelance Client
- Researched and documented the AWS cloud architecture needed for deploying the app back end to periodically ingest data from a government dataset, run a data processing pipeline, and store that data for easy access.
- Scoped React Native work based on Figma screens and investigated and documented needed tooling and libraries.
- Provided context for chosen technologies and implementations, suggested alternatives, and shared general software development best practices.
Experience
Educate to Space
http://educatetospace.comAI Assisted Moderation
https://www.foodnoms.com/blog/ai-assisted-moderation/MissionHub
https://www.missionhub.comI helped rewrite the existing mobile app and align it with the new product direction. I worked with the product and design teams to implement new features and turn Figma designs into beautiful screens. I had front-end technical lead responsibilities to help make technology decisions, mentor coworkers, and improve code quality. I helped migrate MissionHub to React Hooks, TypeScript, and GraphQL. And I implemented auth, onboarding, reminders, and community features.
Education
Bachelor's Degree in Computer Engineering
University of California Davis - Davis, CA, USA
Skills
Libraries/APIs
React, AWS Amplify, Node.js, REST APIs, OpenAI API, JSON API, React Navigation, GraphQL API, Drizzle, Chart.js, Stripe, Web3.js, PostgREST, NativeWind, Google Maps, React Query, Coinbase API
Tools
GitHub, Amazon Elastic Container Service (ECS), ChatGPT, Zapier, Expo, Claude Code, Babel, Webpack, Jira, Travis CI, PCB Layout, Autodesk Fusion 360, Git, CAD, Google Analytics, Amazon CloudFront, n8n, Sentry, AWS IAM, Drizzle ORM, Claude, HelpScout, Figma, Prisma, Knex.js, AWS SDK, Auth0, GitLab, Prettier, Amazon Simple Notification Service (SNS), Amazon Simple Queue Service (SQS), Terraform, MQTT, AI SDK
Languages
JavaScript, TypeScript, GraphQL, CSS, HTML, HTML5, SQL, C, Rust, Embedded C, C++, PHP, Java, Python
Frameworks
React Native, Next.js, Jest, Tailwind CSS, AngularJS, Tachyons CSS, Koa, Material UI, OAuth 2, Redux, Botpress.io, Agentic Frameworks, Serverless Framework, Express.js
Paradigms
DevOps, Responsive Web Design (RWD), Mobile Development, Application Architecture, Code Refactoring, Agile, REST, Unit Testing, Back-end Architecture, App Development, UI Design, Continuous Integration (CI), Serverless Architecture, Microservices, Agile Software Development, Agile Product Management
Platforms
Amazon Web Services (AWS), Vercel, Docker, Visual Studio Code (VS Code), Linux, AWS IoT, Netlify, AWS Lambda, Firebase, iOS, Android, Contentful, Blockchain, Mobile, Amazon EC2, DigitalOcean, Embedded System Design (ESD), STM32, Raspberry Pi, Bluetooth Low Energy (LE), Calendly, Kubernetes, RevenueCat, Ethereum, Mapbox, Twilio, Google Cloud Platform (GCP), PostHog
Storage
PostgreSQL, Databases, Database Structure, JSON, MySQL, Datadog, Amazon S3 (AWS S3), Redis, SQLite
Other
Apollo, Front-end, Web App Development, CI/CD Pipelines, Mobile App Development, Bluetooth, APIs, API Integration, Code Review, Full-stack, Mobile UX, Architecture, Full-stack Development, Technical Leadership, Nonprofits, Charity, Minimum Viable Product (MVP), Technical Product Management, Software Architecture, OpenAI, Supabase, Back-end, Artificial Intelligence (AI), Websites, AI Tools, Authentication, Large Language Models (LLMs), Web Development, Cloud Storage, User Experience (UX), User Interface (UI), Cloudflare, Front-end Development, Teamwork, Communication, Complex Application User Interfaces (UI), Mobile Applications, RESTFul APIs, Technical Support, IT Audits, Security, SVG, Progressive Web Applications (PWAs), Front-end Architecture, Webhooks, ChatGPT API, Software Development Lifecycle (SDLC), Website CMS, Analytics, Integration, JSON REST APIs, Data Engineering, Event Marketing, API Design, Back-end Development, AI Integration, SDKs, System Architecture, ECS, Bluetooth Low Energy (BLE), OAuth, User Authentication, Google Search Console, React Hooks, Responsive UI, Application State Management, Infrastructure, AI Product Strategy, GitHub Actions, Internet of Things (IoT), ESP32, Electronics, Apollo Server, Embedded Development, Cryptocurrency, CSS Grid, Serverless, Smart Devices, Cloud, Donations, Embedded Systems, Product Ownership, Firmware, Project Consultancy, OpenAI GPT-3 API, OpenAI GPT-4 API, Deno, Embedded Hardware, Embedded Software, Hardware, Headless CMS, Mobile Apps, Payment APIs, Startups, User Profiles, Row-level Security (RLS), Tailwind UI, Prompt Engineering, IoT Protocols, Team Management, CTO, Fractional CTO, Single Sign-on (SSO), Payment Gateways, Early-stage Startups, Solution Architecture, Push Notifications, GPIOs, I2C, LoRa, Agentic AI, AI Agents, Monitoring, WebSockets, Leadership, AWS Cloud Architecture, Data Visualization, Data Structures, Amazon API Gateway, Retrieval-augmented Generation (RAG), Dashboards, eCommerce, Open Source, Amazon Route 53, Vector Databases, Microcontrollers, Hardware Engineering, Systems Engineering, Communication Protocols, Network Security, App Store, Google Play Store, TCP/IP, Offline Data Synchronization, Local Networking, Supabase Auth, Amazon RDS, Interactive Dashboards, Real-time Data, Multi-agent Systems, Pgvector, Firmware Development, Customer Relationship Management (CRM), Agentic RAG Systems, AI-generated Code, AI-assisted Development, PCB Design, Printed Circuit Board (PCB), GraphQL Code Generator, Crypto, Non-fungible Tokens (NFT), Smart Contracts, Ethers.js, Scrum Product Owner, Amazon Kinesis, Electrical Engineering, Digital Hardware Design, OpenAI SDK, Web3, Okta, PID Controllers, Motor Control Systems, Hono, Neon Signs, Cryptocurrency Wallets, Uniwind, Kysely, Google Nearby, React Native Reanimated, Hybrid Public Key Encryption (HPKE), Better Auth
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