Aaron
Coplan

I’m a staff engineer at Meta building the systems that let our apps work together — currently shipping cross-app experiences between WhatsApp, Facebook, and Instagram.

Aaron Coplan

Product engineer, with platform depth.

Currently Android Tech Lead for Cross App Experiences at Meta, using AI to deliver seamless product experiences to 3 billion users. I’m passionate about building user-facing products but never afraid to get my hands dirty in the infrastructure underneath them. In my free time I love tennis, travel, and reading.

Experience.

2025—present

Staff Software Engineer · Cross App Experiences · Meta

Led a 10-engineer effort across two orgs to ship Meta’s account switcher in WhatsApp, adding 1M+ monthly users. Architected the Android service between WhatsApp and Facebook/Instagram — foundational infrastructure that powers cross-app linking, crossposting, and new-user growth, key revenue drivers for Meta.

2023—2025

Staff Software Engineer · Facebook Design Systems · Meta

Led engineering on Facebook’s 2023 brand refresh — new Reactions, a ground-up icon redesign, and a fresh color palette — which became the template for every Meta visual refresh since. Built the design-token platform beneath it (the source of truth for visual design across 5 design systems and 6 UI frameworks) and shipped the Newsfeed redesign that drove $365M in annual incremental revenue.

2019—2023

Software Engineer → Senior Software Engineer · Facebook Product Quality · Meta

Built and owned UI Quality Review, Meta’s automated tool for catching accessibility and usability bugs across iOS, Android, and Web. Embedded it into the company’s code-review process, scaling adoption ~10× year-over-year to 1,400+ code changes and 2,000+ design screens reviewed.

Personal projects.

PROJECT · 01

shuffler

A better shuffle for Spotify — genuinely random, multi-source, and tunable. Native iOS, playing through Spotify’s SDK.

Swift · SwiftUI · Spotify SDK
TestFlight
PROJECT · 02

what2wear

An AI personal stylist. Suggests outfits from your real wardrobe based on weather, calendar, and recent wear — reasoning runs on Claude.

React Native · Spring Boot · Claude
TestFlight
PROJECT · 03

paaron

A Claude-powered personal assistant. Reads my email, calendar, and to-dos, thinks overnight, and sends a synthesized morning briefing.

Python · Claude · sqlite-vec · GCP
Private
PROJECT · 04

waterfall

A brand-new compiled programming language with powerful static analysis, transpiling to multiple targets: JavaScript, Python, and C99.

Kotlin
GitHub
MORE ON GITHUB

Skills

Languages
Swift · Kotlin · TypeScript · JavaScript · Java · Python · SQL · Hack/PHP
Frameworks & Platforms
React · React Native · Spring Boot · GraphQL · PostgreSQL · AWS · GCP
AI
Claude Code · Anthropic SDK

Say hello.

Don’t hesitate to reach out for any reason — my inbox is always open!

Email me