SELECTED · 07 ENTRIES · 2023 — 2026

Things
I have
shipped.

A small set of projects across AI, iOS / SwiftUI products, React / Express tools, Java backend services, REST APIs, and data visualization. Most were team-led; the byline below tells you the role.

[A]

Selected Work

~/projects/*.md
[01]

Coin · iOS Spending Tracker

Privacy-focused iOS app · Swift / SwiftUI

Built a local-first spending tracker with fast expense entry, monthly budgets, category analytics, widgets, Siri Shortcuts, multi-currency reporting, JSON import/export, and on-device Apple Intelligence spending insights with a deterministic fallback.

WHEN
May 2026 — present
STACK
Swift SwiftUI SwiftData Siri
GITHUB
iJustinn/Coin
[02]

Body · iOS Health Visualization

Privacy-focused health app · SwiftUI / HealthKit

Built a local-first Apple Health dashboard for workouts, Activity Rings, sleep, energy, body measurements, daylight, steps, and vitals, with WidgetKit calendar widgets, range-based charts, workout history, and local snapshot storage for widget data.

WHEN
May 2026 — present
STACK
Swift SwiftUI HealthKit WidgetKit
GITHUB
iJustinn/Body
[03]

JobMuse · Career Ops GUI

AI-assisted career-ops workspace · React / Express

Built a local-first career-ops workspace where the backend owns provider keys, runs AI-assisted scans and report jobs against local application data, streams server-sent logs back to the GUI, and connects those results to application tracking, pipeline editing, and script runners.

WHEN
May 2026 — present
STACK
React Express Vite Node
[04]

NASA Space Apps Challenge

Team Leader · backend · global hackathon

Built a Java backend with Maven and REST-style APIs against multiple official NASA data sources. Implemented real-time / manual fetching, collaborated on Monte Carlo simulation support, and defined API contracts for the frontend visualization layer.

WHEN
Sep 2025 — Oct 2025
STACK
Java Maven REST JS
[05]

Toxi-Can

Team Leader · Visualizing Canada's industrial pollutant releases

Processed NPRI and Statistics Canada boundary data with R (tidyverse, sf, rgdal), then built an interactive multi-page visualization site with Leaflet maps, Plotly, D3.js and scrollytelling. Designed a narrative experience to make complex environmental risk data understandable to non-technical readers.

WHEN
Oct 2024 — Dec 2024
STACK
R D3.js Leaflet Plotly
[06]

U.S. Residential Real Estate Trends

Course Project · 20-year statistical analysis

Data collection and cleaning with Zillow Research housing datasets in R (tidyverse, dplyr, tidyr) — missing value handling, inconsistency fixes, and time-series alignment across regions and housing types. Built statistical models over 20 years of price history and developed clear ggplot2 visualizations to communicate long-term trends and regional differences.

WHEN
Mar 2024 — Apr 2024
STACK
R ggplot2 dplyr
[07]

Media Manager · Spotify API

Team Leader · Java desktop client

Tested Spotify API workflows in Java, built GUI features with Java Swing, and implemented core use cases including the song-add and search modules.

WHEN
Sep 2023 — Dec 2023
STACK
Java Swing Spotify API
[B]

Experience

~/experience.log

Xiaomi Proretail

Backend Developer Intern

Added clue-statistics modules with drill-down detail, expanded clue ownership and filter analysis by store and employee, and optimized SQL logic to reduce clue-count response time by approximately 100 ms.

Jul 2024 — Aug 2024
[C]

Leadership

~/leadership.md

FRC — FIRST Robotics Competition

Beijing, China · Team Leader, Team 8204

Founded and captained Team 8204 in high school. Previously served as robot driver and engineer for Team 5451, with top-four finishes at international competitions in Sydney, Shanghai, and Pittsburgh.

Jul 2017 — Jun 2021
[D]

Continue

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