David Xiao
Web Developer, Secco Squared
Full-stack web applications, lead-generation flows and data-driven optimization.
Rebuilt a video site's lead funnel, reducing costs by $1,300+ monthly while improving conversion.
Approach & current work
I'm a Web Developer at Secco Squared focused on full-stack web applications, lead-generation flows, and reliable delivery. Fluent across TypeScript, React, Next.js, Node.js, Python, Go, and C, I like hard, load-bearing work: A/B testing and optimizing pages, tightening REST APIs, and making systems cheaper to change.
At Secco Squared I run A/B tests on production pages, optimize lead-generation flows with data-driven decisions, build client integrations and in-house tooling, and rebuilt a video site's lead funnel — cutting costs by $1,300+ monthly. On the side I build Kyarafit (offline-first TypeScript monorepo for web + mobile), OutfAI (a recommendation engine with explainable rationales), and RandCompile (a GCC plugin hardening Linux kernel binaries).
- TypeScript
- JavaScript
- Python
- Go
- C
- C++
- SQL
- PHP
- Bash
- React
- React Native
- Next.js
- Node.js
- Express.js
- FastAPI
- Expo
- PostgreSQL
- MySQL
- SQLite
- Convex
- Firestore
- Vitest
- Jest
- Playwright
- Docker
- GitHub Actions
- Jenkins
- GCP
- Vercel
- Heroku
- Linux
Work
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Personal Portfolio
xiaoOS: a Go + TypeScript portfolio with a procedural city, windowed applications and independently readable project and resume documents.
How it’s built
Built from scratch with Go and Gorilla Mux serving semantic HTML templates, then enhanced with vanilla TypeScript. One lazy-loaded three.js city carries the camera from the boot sequence into the desktop; applications open as windows on desktop and documents on mobile. GSAP coordinates the cinematic, with a static acquisition sequence for reduced motion and an SVG fallback when WebGL is unavailable. The project index supports filtering, technology relationships and live captures of locally hosted games. A LaTeX source supplies the downloadable resume; esbuild, Tailwind CSS and Docker support the Heroku build.
- Go
- TypeScript
- HTML/CSS
- Tailwind CSS
- LaTeX
- Docker
- Heroku
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Kyarafit
Cross-platform cosplay wardrobe app — TypeScript monorepo (Next.js web, Expo RN mobile) on a Convex reactive backend with Stripe-gated tiers.
How it’s built
A cross-platform cosplay wardrobe and outfit planning app. Organize costume pieces in a digital closet, link them into character builds, plan conventions day by day, and auto-generate smart packing lists. Built as a TypeScript monorepo with a Next.js web app, React Native (Expo) mobile client, shared design system, and Convex serverless backend with real-time reactive queries. Features offline-first mobile storage via SQLite, Better Auth authentication with Google OAuth, tiered subscriptions via Stripe.
- TypeScript
- React Native
- Next.js
- Expo
- Convex
- FastAPI
- Python
- TailwindCSS
- Docker
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OutfAI
Wardrobe-first AI stylist redesigned around an editorial landing page, closet-aware recommendations, and clear outfit reasoning.
How it’s built
A Next.js + Convex wardrobe app that turns closet uploads, mood, weather, calendar, and preferences into explainable outfits. The May 2026 redesign moved OutfAI from a dashboard-first feel to a full-bleed editorial landing page with a styled brief, generated look, and why-it-works panel that makes the product value legible before sign-up.
- Next.js 15
- React
- TypeScript
- Tailwind CSS
- Convex
- Better Auth
- Framer Motion
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ForgeArena
Gamified fitness platform — RPG-style avatar progression and social gym competition, built as a multi-semester TypeScript + Go team project.
How it’s built
A gamified fitness platform blending avatar evolution with social gym competition. Currently in development as part of CSCI-40500 coursework, this project combines fitness tracking with RPG-style character progression and social features. Repository is private within class organization.
- TypeScript
- Go
- React
- PostgreSQL
Experience
-
Web Developer at Secco Squared
- Rebuilt a video site's lead funnel, reducing costs by $1,300+ monthly while improving conversion
- Run A/B tests on production pages and optimize lead-generation flows through data-driven decisions
- Build Next.js features and client integrations across production web projects
- Develop in-house tooling to streamline team workflows
- Next.js
- React
- TypeScript
- A/B testing
- Lead generation
- Client integrations
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Software Engineer Intern at Unadat
- Decomposed a legacy PHP/JavaScript monolith into modular microservices, cutting feature delivery time by 25% across 6 production releases
- Optimized 10+ REST endpoints with input validation and query batching, reducing average response time by 15%
- Shipped a reusable React component library adopted by 3 product teams, eliminating duplicate modal and form implementations
- Hardened backend endpoints against SQL injection and XSS by introducing parameterized queries and centralized input sanitization
- JavaScript
- PHP
- React
- MySQL
- RESTful APIs
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Bachelor of Arts, Computer Science · CUNY Hunter College
Get in touch
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