Renchi Liu

System Builder.

I design and ship systems across AI, backend architecture, and mobile products, turning fuzzy workflows into useful software.

  • AI systems
  • Backend architecture
  • Mobile products

Portfolio

Selected Work

All projects

iPhone + Apple Watch App

膳环 (MacroHalo)

A local-first food and nutrition logging app for iPhone and Apple Watch, with photo-based AI nutrition estimates, reviewed meal records, CSV backup, widgets, Live Activities, and bilingual App Store support pages.

  • iOS
  • Apple Watch
  • Local-first
  • AI nutrition

iPhone App

Medication Tracker / 药不能停

A private, on-device medication check-in and reminder app for iPhone, with local records, daily reminders, and bilingual support and privacy guidance.

  • iPhone
  • Local-first
  • Health tooling

Reusable Prompt System

Prompt Library

A lightweight library of reusable prompts for engineering, writing, and systems thinking, designed to stay easy to browse, copy, and maintain.

  • Prompt design
  • AI workflows
  • Knowledge systems

Writing

Latest Writing

Full writing archive

Where Should the LLM Live in an Agentic Workflow?

A practical look at where LLMs belong in agentic workflows, and why production systems separate planning, execution, rendering, memory, evaluation, and guardrails.