XW

Open to global remote & relocation

Xinheng Wang

Full-Stack & AI Engineer

Product-minded engineer shipping production cross-platform apps and web platforms from scratch — bridging rigorous CS and ML foundations with high-velocity execution.

Shanghai, China / Hong Kong, China / Kunming, ChinaGlobal remote & relocationHK Work Visa (TTPS)
Scroll to explore

01 — About

About me

Hi, I'm Xinheng. I recently graduated Magna Cum Laude from the University of California, San Diego with a double major in Mathematics-Computer Science and Cognitive Science (Machine Learning Specialization), holding a 3.97 / 4.0 GPA.

I am a product-minded engineer with end-to-end experience building and shipping production cross-platform applications and web platforms from scratch. I bridge rigorous computer science and machine learning foundations with high-velocity product execution.

GPA
3.97 / 4.0
Degrees
Math-CS + Cognitive Science (ML)
Shipped
iOS · Android · Web Admin
Based in
Shanghai, China / Hong Kong, China / Kunming, China

02 — Projects

Featured projects

Production systems and research work, from app stores to surprisal curves.

01

MySurro

Cross-platform surrogacy app & web admin console

A production system with mobile apps for surrogates and intended parents, plus a web admin for agency staff. I translated the founder's requirements into architecture, implementation, QA, and official Apple App Store / Google Play releases.

React NativeExpoNext.jsTypeScriptSupabase (PostgreSQL)EAS BuildEAS Update (hot updates)Tailwind CSS (admin UI)Vercel
Onboarding
Onboarding
Match progress
Match progress
Medical appointments
Medical appointments
Admin — applications
Admin — applications
  • iOS & Android

    Shipped with Expo / EAS. User journeys cover applications, match milestones, medical reports, IVF/OB appointments, and reimbursement claims.

  • Web admin

    Next.js (TypeScript) on Vercel, with role-based access for Admin, Branch Manager, and Finance Manager (read-only payments).

  • Data & auth

    Supabase PostgreSQL with RLS on the mobile client, server-side auth on the admin, and Realtime for match updates and notifications.

  • Release

    EAS production builds for store binaries; Expo OTA for JavaScript-only fixes without a full store resubmission.

02

Transformer LLM sensitivity to world-knowledge violations

LLM interpretability, semantic surprise, and neurocognitive alignment

Investigating how causal language models respond to physical common-sense violations, and how their predictive distributions line up with human brain responses.

PyTorchHugging Face TransformersGPT-2PythonSeabornPandas
Surprisal distribution — plausible vs. violation
Surprisal distribution — plausible vs. violation
  • Minimal pairs

    Formulated minimal pair test sets (e.g. key vs. banana) to analyze GPT-2's sensitivity to physical common-sense violations.

  • Surprisal analysis

    Extracted next-token output logits and computed Shannon surprisal (−log₂ p), showing semantic anomalies yield 3× higher surprisal (M ≈ 11.1 vs. 4.1).

  • Cognitive parallel

    Drew computational parallels between LLM predictive distributions and human N400 ERP brain responses.

03

High-precision agricultural computer vision classifier

Deep CNN for multi-class agricultural image classification

A deep convolutional network built for large-scale agricultural imagery, paired with an automated preprocessing pipeline.

PythonKeras / TensorFlowOpenCVKeras Tuner
Feature correlation matrix
Feature correlation matrix
  • Accuracy

    Engineered a deep CNN classifying 75,000+ agricultural images with 98.5% test accuracy, outperforming standard baseline models by 14%.

  • Pipeline

    Implemented an automated preprocessing pipeline with OpenCV for data augmentation, geometric feature extraction, and image normalization.

03 — Experience

Work experience

Shipping software, evaluating frontier models, and teaching math.

  1. Babytree Surrogacy

    Oct 2025 – Present

    Full-Stack Software Engineer (Contract / Lead Developer)

    Ontario, CA / Remote

    • Served as the sole engineer building and maintaining MySurro (iOS, Android, and Web Admin Console).
    • Engineered full-stack features, managed database architecture on Supabase, and handled end-to-end app store deployments.
  2. Handshake AI

    Aug 2025 – Sep 2025

    AI Model Evaluation Fellow (MOVE Fellow)

    Remote (San Diego, CA)

    • Contracted on Project Castor (QA Bench) evaluating static web applications against multi-node interaction rubrics for leading frontier AI labs.
    • Assessed UI component dependencies, event handlers, and model failure modes to generate structured benchmark datasets for RLHF model alignment.
  3. Mt. San Antonio College

    Jan 2023 – Feb 2023

    Academic Support & Achievement Center Tutor

    Walnut, CA

    • Tutored undergraduate students in Advanced Calculus and Statistical Analysis to improve course retention and pass rates.

04 — Skills

Technical skills

The toolkit I reach for across product, platform, and model work.

Languages

TypeScriptJavaScriptPythonSQLC++JavaHTML/CSSRMATLAB

Frontend & Mobile

React NativeExpoNext.jsReact.jsTailwind CSS

Backend & Cloud

Node.jsSupabase (PostgreSQL, Auth, Storage, Realtime, RLS)VercelRESTful APIsEAS BuildEAS UpdateLinux/Unix

AI & Machine Learning

LLM EvaluationTransformer ArchitecturesPrompt EngineeringRLHF Data CurationRAGPyTorchTensorFlowKerasScikit-learnOpenCV

Developer Toolchain

GitCursorApp Store ConnectGoogle Play ConsolePostman

05 — Education

Education & honors

Mathematics, computer science, and the cognitive science of learning machines.

University of California, San Diego (UCSD)

Sep 2023 – Sep 2025

B.S. Mathematics-Computer Science & B.S. Cognitive Science (ML Specialization)

GPA 3.97 / 4.0 · Magna Cum Laude · Provost Honors (all quarters)

Mt. San Antonio College

Jan 2021 – Jun 2023

A.S. Mathematics for Transfer (Honors)

GPA 4.0 / 4.0

Let's build something impactful

Open to full-time roles, global remote work, and relocation. The fastest way to reach me is email.

nobelwang61@gmail.com