available for new work

Peter Liu

Full-stack & AI Engineer

I build production systems end to end — from greenfield web platforms serving tens of thousands of users to autonomous LLM agents and self-hosted AI infrastructure.

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📍 Rocklin, CAgithub.com/onhoutlinkedin.com/in/peter-liu

01 — About

A bit about me

Full-stack software engineer with 10+ years shipping production systems across Ruby on Rails, Python, PHP/Laravel, and modern JavaScript (React, Vue, Angular).

Recent focus on AI/LLM integration — I've built and deployed both user-facing RAG chatbots and internal autonomous agents using Claude, Qwen, and Autogen, including self-hosted open-source models on vLLM for cost control and data residency.

Comfortable as a tech lead or individual contributor: I've built greenfield systems from scratch, owned infrastructure, and mentored engineers.

Education

  • California State University, East Bay

    B.S. Computer Science

    2012 – 2014

  • Coding Dojo

    3 Full-Stack Black Belts (MEAN, Python, Ruby) · 10/10 MEAN exam

    2015

02 — Experience

Where I've worked

Software Engineer · CalMHSA

Sep 2021 – Present

California Mental Health Services Authority

  • Co-led a greenfield team building the statewide peer-supporter certification platform (tens of thousands of users) on Laravel + Vue + Auth0, with Docker infra and Jenkins CI/CD.
  • Shipped a Claude-powered RAG chatbot grounded in program docs that reduced repetitive support tickets.
  • Built an Autogen-based agent for structured PDF data extraction from certification paperwork.
  • Led migration to self-hosted open-source LLMs (Qwen3.6) for cost and data residency. Mentored junior engineers and set architecture patterns.

Co-Founder / Engineer · SimpoCloud Inc.

Jan 2021 – 2023
  • Built a SaaS point-of-sale platform from zero on Ruby on Rails for independent retail merchants.
  • Designed a custom LTE receipt printer (Raspberry Pi + scanner + thermal printer) controlled from the web app via WebUSB / Web Bluetooth.
  • Owned the full surface: backend, frontend, hardware, and deployment.

IT Systems Manager · ASC Therapeutics Inc.

Sep 2020 – Sep 2021

spin-off from Applied StemCell

  • Sole IT for the spin-off — managed 5 servers and all research workstations for the gene-editing team.
  • Customized a Python ERP for gene-editing workflow tracking.
  • Replaced commercial SaaS with self-hosted open-source equivalents (Docker), saving thousands per year.

Web Application Developer II · Applied StemCell Inc.

Jul 2018 – Sep 2020
  • Maintained and extended a Ruby on Rails internal scientific platform for bench scientists.
  • Built a gene visualization and reporting tool (D3.js + Ensembl API) and a customer-facing React portal with real-time ActionCable updates.
  • Programmed Opentrons OT-2 liquid-handling robots in Python to automate wet-lab SOPs.

Web Developer / Financial Analyst · WOW88 Strategies

2018 / 2020 – 2022
  • Built quantitative trading strategies and indicators in C# (.NET) for MultiCharts and NinjaTrader.
  • Migrated a legacy WordPress site to a full-stack Django application.

Web Developer I · Madsen, Kneppers & Associates

Aug 2015 – Jan 2018
  • Modernized a forensic-engineering case-management front-end (prototype.js → Bootstrap + Angular.js).
  • Built REST APIs on a custom PHP framework and interactive analytics dashboards with D3.js, Crossfilter, and DC.js.

03 — Projects

Selected work

A few things I've designed, built, and shipped — from statewide platforms to AI agents and custom hardware.

CA Peer Certification Platform

featured

Co-led a greenfield team building California's statewide peer-supporter certification platform — public registration, exam workflows, certification issuance, and an internal staff admin dashboard. Serves tens of thousands of users.

app.capeercertification.org ↗
LaravelVueAuth0JenkinsDocker

Claude-Powered RAG Chatbot

featured

A retrieval-augmented chatbot that answers user questions about the peer-certification process — eligibility, application steps, exam policies — grounded in CalMHSA's program documentation. Cut repetitive support tickets.

Claude APIRAGpgvectorPython

Autogen Document-Extraction Agent

An internal autonomous agent that extracts structured fields from submitted certification paperwork — applications, transcripts, attestations — so staff no longer hand-transcribe forms.

AutogenLLM agentstool callingPDF

Self-Hosted LLM Migration

Led an in-house migration to self-hosted open-source LLMs (Qwen3.6 on vLLM) for cost control and data residency, replacing external API calls on internal-only workflows.

QwenvLLMself-hostedinfra

SimpoCloud POS + LTE Hardware

Built a SaaS point-of-sale platform from zero on Rails, used by independent retail merchants — and designed a custom LTE-enabled receipt printer (Raspberry Pi + thermal printer + scanner) driven straight from the web app over WebUSB / Web Bluetooth.

Ruby on RailsRaspberry PiWebUSBHardware

Gene Visualization & Lab Automation

Built a gene visualization and reporting tool (D3.js + Ensembl API) for bench scientists, plus a React portal with real-time updates over ActionCable, and programmed Opentrons OT-2 liquid-handling robots in Python to automate wet-lab SOPs.

D3.jsReactPythonOpentrons

04 — Skills

Tools I work with

Languages

PythonRubyJavaScriptTypeScriptPHPC#SQL

Backend

Ruby on RailsLaravelDjangoFastAPINode.js

Frontend

ReactVueAngularNext.jsD3.js

AI / LLM

Claude APIOpenAIQwen / vLLMAutogenRAGpgvectorAgentic workflows

Infrastructure

DockerJenkinsAuth0AWSLinuxRaspberry Pi

Data

PostgreSQLMySQLSQLiteETL pipelinesCrossfilter

05 — Contact

Let's build something

Open to full-stack and AI engineering roles. The fastest way to reach me is email.

peterliu21689@gmail.comGitHub ↗LinkedIn ↗

(916) 888-8268 · Rocklin, CA