Hello, I'm Alvin

Full-Stack Developer & AI Developer

Building scalable web applications and intelligent AI-driven solutions to power the next generation of digital experiences.

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Profile

Alvin Xu

AI/ML & Full-stack — M.S. in Computer Science

yingjiex@usc.edu
linkedin.com/in/yingjie-xu-435a111b5
Evanston, IL · open to relocate
Open to new roles
University of Southern California — M.S. in Computer Science
Aug 2023 — May 2025 · Los Angeles, CA
McGill University — B.Sc. (Honours) in Computer Science
Sep 2019 — May 2023 · Montréal, QC
End-to-end data & ML pipelinesNestJS/Node microservices & REST APIsBackend & systems optimizationLLM fine-tuning (LoRA / QLoRA)Scalable indexing & retrieval (video, genome search)Auth & DevOps (OAuth2/JWT, CI/CD, Kubernetes)
Languages
PythonJavaCC++TypeScriptJavaScriptHTML/CSSKotlin
ML / Data
PyTorchTensorFlowPandasNumPyMongoDBDB2OpenCV
Frontend & Backend
ReactAngularNext.jsNestJSNode.jsExpressDocker
DevOps & Workflow
AzureAWSGitHub ActionsCI/CDAgile/Scrum,DockerMatlab
Focus Now
  • AI assistant/character demo: streaming dialogue with long-term memory; local 7B for dev, API as fallback
  • Document Q&A you can measure: embeddings in Postgres (pgvector), combine semantic + keyword search, small offline test set
  • Auth & permissions: Keycloak OIDC integrated with NestJS; role checks (RBAC) and basic audit logs
  • Delivery & reliability: Docker + GitHub Actions; structured logs + light tracing; background jobs with retries/backoff
Strengths
  • Backend-first delivery: NestJS/Node services · PostgreSQL/Prisma modeling
  • Practical AI integration: OpenAI + local 7B calls · retrieval pipelines
  • Frontend that ships: Next.js/React · Tailwind/shadcn for clean UIs
  • Deploy & debug: Docker/Nginx · AWS/Azure basics · logs/traces for triage
Principles
  • Ship small; verify with metrics & evals (latency, cost, quality)
  • Keep designs simple & explicit: clear APIs, tests, and documented trade-offs
  • Assume failure; make it safe: idempotency, timeouts, retries/backoff, rate limits
  • Privacy & security by default: least privilege, secrets hygiene, audit trails
Selected Work
Investment Platform (Full-stack + SwiftUI)
AngularNodeMongoDBSwiftUI

Full-stack investment platform with SwiftUI iOS app and Node.js/Express backend, integrating Finnhub/Polygon APIs for live market data. Supports watchlists, stock search, interactive charts, and P/L tracking.

Integrated Water Resources Monitoring Platform
DB2Time-seriesIndexingClassical ML

Modeled DB2 schema for multi-station hydrology time series; designed indexes for range queries; built KNN/Naive Bayes/SVM baselines for forecasting.

Video Frame Hashing & Search
OpenCVpHashIndexing

Scalable perceptual-hash indexing with tolerant matching for deduplication and archive retrieval across large media datasets.

Operating Systems: File System & Disk Driver
COS/KernelFATDrivers

Built a file system module and disk driver in C: on-disk FAT structures, partitioning/mounting, and a high-level API for read/write operations.

Named Entity Recognition (NLP)
BiLSTMTransformerGloVeNLP

Implemented NER with BiLSTM/Transformer and GloVe embeddings; improved accuracy and enabled large-scale text analytics & tagging.