James Hart

Principal engineer who builds and ships daily with parallel AI coding agents (Conductor with Claude and Codex), with long-standing production discipline to keep quality high. Twenty years of web experience, including sixteen years of Ruby on Rails and more recently two years of Next.js. A true full-stack engineer across back-end optimization, infrastructure, and rich front-end apps, with a penchant for keeping it simple. Engineering leader who helped grow a team from 5 to 35 engineers, has conducted 200+ technical interviews, and has helped build hiring processes on four teams. A voracious learner who enjoys working with like-minded people.

GitHub hjhart
LinkedIn hjameshart

Skills

AI Tools
Conductor, Orca, Claude, Codex
Front-End
TypeScript, Next.js (2 years), React, Turbo, TailwindCSS, SwiftUI, Kotlin, ViewComponent, React Native
Ruby
Rails, Sidekiq, RSpec, Capybara
Operations
Docker, Aptible, Github Actions, Bash, Heroku
Data Stores
PostgreSQL, Redis, ElasticSearch
Editors
VSCode, XCode, Android Studio

Experience

Clarity Pediatrics

Principal Engineer Jan 2025 - Present

Led the build of the redesigned member web app. Re-architected testing infrastructure. Reduced number of tickets per day for Operations by building more self-scheduling flows for our members.

  • Scaled the pediatric care platform to 4,500+ billable sessions and $520K in revenue per month.
  • Built platform support for a new obesity-care service line, which grew from roughly 100 to over 250 referrals a month at about 2.5x the margin of our existing behavioral-health groups.
  • Owned production reliability. Cut slow query times, identified and removed replication latency, and upgraded end-of-life datastores, with zero unplanned outages.
  • Built an AI-assisted development workflow that runs several coding agents in parallel (Claude, Codex, Conductor, Orca), tripling my weekly commits (median 3 to 9) and the features I shipped from 2025 to 2026.
  • Developed an interview process that assesses candidates for AI skills and ran it with 30+ candidates, hiring 3 engineers.

Brightline Health

Principal Engineer Jun 2020 - Jan 2025

Founding engineer at Brightline, a pediatric mental health company. Stack: Rails, ViewComponent, TypeScript, Tailwind CSS.

  • Helped launch the initial member- and staff-facing app, which gave over 30k parents and children access to mental health care.
  • Helped devise the engineering hiring plan and grew the team from 5 to 35 engineers, personally interviewing dozens of candidates and shaping the technical bar and culture.
  • Supported the launch of the iOS app (10k+ downloads), then led the launch of the Android app.
  • Built and maintained the CI/CD pipeline, cutting total build time from 75 minutes to 10.

EggWich iPhone and Android App

Creator and Developer Jan 2024 - Present

Highlights breakfast sandwiches and burritos in Seattle, with a focus on small restaurants run by Black, Latinx, women, and LGBTQ owners. Shipped to both app stores using Rails, RSpec, Hotwire, turbo-ios and turbo-android. Originally built in 2010 as an iPhone app for San Francisco.

Voom Flights, an Airbus Company

Principal Engineer Jul 2018 - May 2020

Worked with engineers and designers on the product team and acted as liaison to the leadership team. Mentored engineers through pairing, helped the team make hard technical decisions, and unblocked bottlenecks. Optimized CI/CD to ship faster and helped grow the team from 4 engineers to 14. Built a Rails / React web app and a React Native app.

Wanelo

Director of Engineering Jul 2013 - Apr 2018

At Wanelo, I led the engineering team for numerous years in both application development and platform operations. Under the direction of the CEO and the product team, I advised product owners how we should build our numerous products. I led the team that built and maintained our marketplace for selling products through Shopify. During our growth period, I helped build scalable solutions to handle user growth by sharding postgresql for our user saves. When our user base was declining, I helped advise the company to downgrade our servers and other third-party services to go from $115k to $60k in monthly operating costs.

RPX

Senior Software Engineer Oct 2010 - Jul 2013

Became the lead engineer on the client-facing Ruby on Rails application. Spent six months at Pivotal Labs learning agile methods and TDD. Led front-end development of a single-page Backbone application, built a gem to share one database across several Ruby applications, and built an API between Postgres stored procedures and Rails.

Lean Startup Productions

Freelance Software Engineer Aug 2013 - Dec 2014

Enhanced the Lean Startup Conference website, built conference software in pure Ruby that matched attendees to mentors (used at Lean Startup Conference 2014 and QuickBooks Connect 2014), and built the editorial site "The How."

Tara Mohr

Freelance Software Engineer Oct 2013 - May 2014

Built and maintained a members-only WordPress site and worked with third-party developers to improve their WooCommerce plugin.

WebKey LLC

Web Developer May 2008 - Sep 2010

Delivered web design and development for clients including Fremont Brewing Company, Washington Green Roads, and Richard Conlin (Seattle City Council), working directly with them on requirements and support.

hjhart.com

Freelance Web Design and Development Aug 2004 - Sep 2010

Freelance web design and development through high school and college, on PHP/MySQL. Clients included Night Owl Lounge, Carso's Pasta, Saga Beverages, and Bainbridge Island Yacht Club.

Volunteering

Beacon Hill International School PTA

Web Developer Sep 2023 - Present

Volunteered my time to make the website more accessible and easier to publish content.

Education

University of Washington

Sep 2005 - Jun 2010
Bachelor of Science - Mathematics

University of Washington

Sep 2005 - Jun 2010
Bachelor of Science - Informatics

Publications

Examining the Relationship Between Pediatric Behavioral Health and Parent Productivity Through a Parent-Reported Survey in the Time of COVID-19: Exploratory Study
JMIR Publications
2022-08-18

I built the COBI app that was used to collect data, which was then synthesized to create this publication.