John Stewart

Director of Engineering | Web Platform Architecture

New York, NY

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Summary

Engineering leader with 13+ years building high-scale consumer sports and media platforms. Currently direct MLB.com’s Web Platform Architecture team, delivering infrastructure and experiences that reach millions of fans across web, native mobile apps, and connected devices — with sharp traffic peaks around marquee events like Opening Day and the Postseason. Proven at defining platform strategy, translating it into technical roadmaps and staffing plans, and growing engineers to execute — while owning business outcomes including a ~66% infrastructure cost reduction. Deep expertise in React/Next.js, Node.js, CDN/edge architecture, and AWS/GCP.

Experience

Director of Engineering – Web Platform Architecture

January 2022 - Present
MLB
New York, NY

Lead the engineering team responsible for MLB.com’s web platform, serving millions of fans during peak baseball season. Platform experiences reach users on the web, inside MLB’s iOS/Android apps (web views and embedded widgets), and on connected TV devices.

Leadership & Strategy

  • •Define platform strategy and translate it into technical roadmaps, sprint plans, and staffing decisions as both engineering manager and technical product owner
  • •Grow and mentor engineers through structured performance reviews, career development planning, and hands-on technical coaching
  • •Established CDN standards and practices adopted by MLB’s mobile engineering organization, extending web platform patterns across iOS/Android infrastructure
  • •Led cross-team capacity planning initiative preparing Kubernetes infrastructure for Opening Day peak traffic — audited cluster configurations across multiple platform teams, modeled compute requirements, and resolved node/pod IP address space constraints; delivered Opening Day with zero capacity incidents
  • •Collaborate cross-functionally with product teams to define platform requirements and technical standards

Business Impact

  • •Drove cost engineering initiative across web platform GCP projects, cutting daily cloud spend ~66% (from ~$3.5K to ~$1.2K per day, ~$840K annualized) while maintaining uptime, product experience, and operational standards
  • •Optimized CDN architecture across multiple providers, improving site performance and reliability while delivering 87.5% CDN cost savings
  • •Created fetcher and cacher libraries standardizing data fetching and app-layer Valkey caching across web applications — improved targeted API call performance by 50% and cut costs 25% in the first adopting application, with rollout expanding across the platform

Technical Achievements

  • •Led team through a disaster recovery initiative enabling multi-CDN and multi-region failover architecture across the web platform
  • •Architected and deployed Kubernetes clusters on GKE, managing multi-environment infrastructure across GCP; coordinated large-scale GKE version migrations with zero downtime
  • •Designed CI/CD pipelines for builds, deployments, and internal processes using Tekton, Argo, and GitHub Actions
  • •Implemented Infrastructure as Code with Terraform across multiple CDNs (Cloudflare, Fastly) and GCP
  • •Created monorepo of core application libraries used by teams across MLB to build web applications
  • •Built internal products enabling content producers to manage backend operations independently, reducing engineering bottlenecks

Senior Software Engineer

January 2020 - January 2022
Instabase
Remote
  • •Led major Webpack rebuild initiative, modernizing build and deployment processes
  • •Spearheaded migration from Flow to TypeScript across the entire frontend codebase
  • •Architected internal component library, accelerating development cycles for engineering teams
  • •Designed and built developer tooling for third-party application development on the Instabase platform
  • •Organized bi-weekly Frontend Guild meetings, fostering knowledge sharing across teams

Senior Software Engineer

April 2019 - January 2020
William Hill
Remote
  • •Developed and shipped mobile sportsbook application for iOS/Android using React and Cordova, including MVP authentication flow with Firebase Auth
  • •Led multistate initiative, architecting dynamic state configuration system based on geographic data with manual fallback selection for gambling compliance
  • •Designed config management system enabling dynamic app behavior based on state-specific regulations
  • •Pitched strategic initiative for unified user accounts across states, consolidating funds management
  • •Modernized deployment architecture using CloudFront, Lambda@Edge, and S3

Senior Software Engineer (Promoted from Software Engineer)

November 2016 - April 2019
MLB
New York, NY
  • •Built first production React application on MLB.com (MLB All-Star Ballot), pioneering modern frontend architecture and establishing frontend development standards
  • •Led development of mlb.com/news, serving high-traffic content during baseball season
  • •Selected to interview and hire 20+ engineers across MLB’s web organization
  • •Architected user account management web app for subscription and personalization features; led web integration for MLB’s Okta implementation
  • •Implemented React server-side rendering for SEO optimization across multiple applications
  • •Spearheaded migration from legacy RequireJS/Bower to modern Webpack/Node.js ecosystem and led CMS migration from legacy system, including multi-platform POC evaluation

Senior Frontend Developer

December 2014 - November 2016
ROAR
New York, NY
  • •Built Elasticsearch-powered analytics dashboard for Chase and a Chromebook demo application for Google; presented client deliverables to company leadership

Digital Developer

December 2013 - December 2014
EFK
New York, NY
  • •Built custom Drupal CMS solutions (PHP/MySQL) for financial institutions and universities; presented solutions, trained client teams, and contributed to new business pitches

Web Developer

May 2012 - December 2013
Alpha Engineering
Maryland
  • •Owned all web initiatives and client projects; built customer-facing PHP/MySQL applications including an event registration portal and sales tracking system

Web Developer

December 2012 - Present
Freelance
Various
  • •USRowing (2016 Olympics): Sole developer for USRowing’s official website, deployed on AWS and live during the 2016 Olympics
  • •CMS: Delivered WordPress and Drupal solutions for diverse business requirements
  • •Commerce & Payments: Built secure payment portals using Node.js, Express, Braintree, and Stripe APIs; created Shopify headless commerce site using Hydrogen/Oxygen with Storefront API

Skills

Languages & Frontend

TypeScriptJavaScriptPHPPythonReactNext.jsHTML5CSS3SASS

Backend & Data

Node.jsExpressREST APIsMySQLElasticsearchPostgreSQLMongoDBRedis/Valkey

Cloud & DevOps

AWSGoogle Cloud Platform (GCP)KubernetesDockerTerraformGitHub ActionsArgo CDTekton

CDN & Edge

FastlyCloudflareLambda@EdgeFastly ComputeCloudflare Workers

CMS & Tools

WordPressDrupalNxWebpackGitJIRA

Education

Bachelor of Arts in Computer Science

St. Mary's College of Maryland

2008 – 2012