lucasch.dev — senior software engineer

Lucas
Chaufournier

Senior Software Engineer — Backend, Product & Platform

I build the systems behind the products people actually use — APIs, data pipelines, and internal platforms for high-scale commerce. Eight years at the seam between platform engineering and product delivery.

Seattle, WA · Open to senior & staff roles

About

Senior backend engineer with 8+ years shipping commerce and platform systems that real customers depend on. Most recently at Block (Square), where I was the DRI for building infrastructure for merchant POS migrations contributing to over $300M in incremental GPV for Square for Restaurants and built internal tooling used by hundreds of engineers every month.

I like the problems that show up when distributed systems meet consumer products: migrations that don't slow down users, APIs that are intuitive, and platforms that get out of the way. I care about the craft, the team, and the product being shipped.

Selected Work

Merchant Factory

internal platform · block

An internal platform that generates production-like merchants in staging on demand. Used every month by hundreds of engineers across Square to build and test against realistic restaurant, retail, and marketplace data — without ever touching production.

Menu POS Migration Pipeline

data pipeline · block

Designed and led the rollout of the backend pipelines that moved restaurant merchants onto Square's next-generation menu platform. Zero-loss cutover across thousands of live merchants — contributing to $300M+ in incremental GPV.

Menu Management APIs

public api · square for restaurants

Evolved the catalog APIs that power menu operations across Square for Restaurants. Focused on reliability under high-volume updates and a developer experience that scales to third parties.

Payment Reporting Infrastructure

analytics · block

Built payment reporting infrastructure on Elastigraph supporting merchant analytics, compliance workflows, and financial reporting across restaurant merchants.

Experience

Block/Square

senior software engineer · menus & back office
  • Led backend infrastructure for restaurant merchants and menu systems; contributed to $300M+ in incremental GPV.
  • Designed merchant menu management APIs for Square for Restaurants, improving reliability and DX for high-volume updates.
  • Built Merchant Factory, now used by hundreds of engineers monthly to accelerate development and testing.
  • Built payment reporting infrastructure on Elastigraph for merchant analytics and financial reporting.
  • Mentored two junior engineers; supported one through promotion.

Capital One

senior software engineer · secrets management
  • Designed backend APIs for internal secrets management built on HashiCorp Vault.
  • Operated high-availability Vault infrastructure on AWS for internal authentication workflows.
  • On call for a mission-critical security platform used across Capital One engineering.

George Washington University

adjunct faculty · computer science
  • Taught Database Systems and Advanced Networking & Distributed Systems.
  • Mentored students on large-scale system design and team software projects.

Veea

backend engineer · edge compute
  • Built backend cloud services in Go for distributed edge devices and remote device management.
  • Led developer ecosystem design, improving onboarding for external developers.
  • Prototyped and shipped computer-vision demos running on edge hardware.

UMass Amherst

graduate research · distributed systems
  • Evaluated hardware and OS virtualization performance at scale (containers vs. VMs).
  • Researched multi-path networking protocols in data-center and edge environments.
  • Built large-scale data visualizations for distributed-system debugging.

Beyond Work

Seattle Social Club

founder · 2022 — present

A Seattle nonprofit I founded and scaled to reduce loneliness through curated social and dating events. 62 sold-out events, 3,398+ attendees, 1,062 newsletter subscribers, 6,300+ Instagram followers — now run by a 5-person board. I build the full-stack apps that keep operations running.

Mentorship

block · gwu

Mentored two junior engineers at Block through design reviews and promotion prep, and served as industry mentor for three senior capstone teams (12 students) at GWU — guiding architecture decisions, code review, and delivery planning to mirror real-world engineering.

Publications

Stack

languages
Kotlin · Java · Go · Node.js · Python · Ruby · Flutter
infrastructure
AWS · GCP · Supabase · Docker · Kubernetes · Terraform · HashiCorp Vault
architecture
Microservices · Distributed systems · REST · GraphQL · Kafka
data
Event-driven systems · Data pipelines
tools
Claude Code · Cursor · Goose