Richard is available for hire
Hire RichardRichard Plotkin
Verified Expert in Engineering
Node.js Developer
White Plains, NY, United States
Toptal member since May 27, 2016
Bio
Richard is a full-stack developer with 25 years of experience building React, Next.js, and GraphQL applications for companies such as UnitedHealthcare, Morgan Stanley, and fuboTV. He built OnePass for 5 million users with a 0.5-second average LCP, cut a dashboard's initial page load by over 70%, and took a production API's sign-in time from 4 seconds to 51 milliseconds. Richard specializes in fintech, healthcare, and entertainment, builds applications, and has spoken on architecture at XtremeJS.
Portfolio
UnitedHealth Group
React, Next.js, NestJS, Redux, GraphQL, Architecture, HIPAA Compliance...
Music Education Company
React, Next.js, TypeScript, Redux, Nx, Node.js, NestJS, Prisma, MySQL, iOS...
Silver Eagle Systems LLC
Angular, JavaScript, CSS, MySQL, Python, TypeScript, NgRx, RxJS, Redux, Nx...
Experience
- Node.js - 11 years
- React - 10 years
- TypeScript - 9 years
- Angular - 6 years
- Next.js - 6 years
- GraphQL - 5 years
- React Native - 5 years
- Large Language Models (LLMs) - 2 years
Preferred Environment
Next.js, GraphQL, AWS Lambda, TypeScript, React, Apollo Client, JavaScript
The most amazing...
...thing I've built is OnePass's per-tier Next.js cache: 5 million users, 0.5-second LCP, years before Next.js shipped the same idea as Partial Prerendering.
Work Experience
Master Engineer
2021 - 2026
UnitedHealth Group
- Rebuilt a platform on Next.js, Apollo Client, and a GraphQL edge service, serving about 5 million users across around 100 membership tiers with an average LCP of about 0.5 seconds.
- Designed a Next.js caching layer that collected GraphQL data from the React tree, pre-rendered per-tier pages with ISR, and rehydrated the Apollo cache on the client.
- Rescued a product launch when data arrived 100x larger than specified, moving processing onto Web Workers and cutting P95 from more than 20 seconds (and crashing) to about 2 seconds.
- Reworked gym and class search for areas with 1,200+ gyms by splitting GraphQL queries into closest-first, cacheable geo-tiles batched with Apollo BatchHttpLink.
- Refactored Apollo Client's cache read and merge logic after launch, making data-heavy pages almost 10x faster.
- Refactored Apollo Client's cache read and merge logic after launch, making data-heavy pages almost 10x faster.
- Designed and wrote the eventing engine behind UHC Mobile push notifications, which helped raise customer satisfaction in the app.
- Wrote React and React Native apps across Optum and UnitedHealthcare products, including OptumRx and messaging, as the main GraphQL schema architect.
- Introduced Apollo GraphOS supergraph federation for APIs and webpack Module Federation for web and mobile, so teams could split monoliths into domain-owned services.
- Led the migration of 900+ developers from Jenkins to shared GitHub Actions in six months, cutting infrastructure and subscription costs by large amounts per year.
Technologies: React, Next.js, NestJS, Redux, GraphQL, Architecture, HIPAA Compliance, React Native, Apollo, TypeScript, Node.js, Nx, Redis, IndexedDB, Server-side Rendering (SSR), HTML5 Web Workers, Storybook, Webpack, Microfrontends, GitHub Actions, APIs, AWS Lambda, Android, Angular, Caching, Continuous Integration (CI), Core Web Vitals, Design Patterns, Figma, Front-end Architecture, Full-stack, Apollo Client, JSON Web Tokens (JWT), JavaScript, Jenkins, Jest, Large Language Model Operations (LLMOps), Large Language Models (LLMs), Mobile, Mobile Web, Multithreading, Natural Language Processing (NLP), Performance Optimization, Python, REST APIs, Redux Toolkit, RxJS, Software Architecture, Swift, TanStack Router, Test-driven Development (TDD), Unit Testing, User Interface (UI), Website Performance, XHTML, iOS, Amazon CloudFront, Amazon Web Services (AWS), GraphQL Federation, Datadog, Event-driven Architecture, Webpack Module Federation, Monorepos, OpenAPI, Push Notifications, Web Performance Optimization (WPO), Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Redux Thunk, Apache HTTP Server, Prompt Engineering, AI Integration, Technical Training, Technical Leadership, GitHub Copilot, Code Review, Code Auditing, Authentication, Authorization, HIPAA, Webhooks, Git
Lead Full-stack and Mobile Developer
2015 - 2025
Music Education Company
- Cut production sign-in from 3–4 seconds to 51 milliseconds, and catalog reads from 715 milliseconds to 4 milliseconds by moving the NestJS API onto private networking, caching hot catalog routes, and indexing sign-in lookups.
- Moved the native iOS app's sign-in and sign-up to a new versioned API, with typed DTOs, Keychain credential storage, and password AutoFill.
- Gated every back-end release with 820 unit tests, 365 API contract tests, performance baselines, and CI checks on each pull request.
- Redesigned iOS CI so a 19-second check gates the 28-minute build, and full builds run only when a pull request changes a build input.
- Built the React and TypeScript web storefront with Redux, redux-query, and normalizr, including browse and home pages with category carousels.
- Migrated the web app from Create React App to Next.js, then restructured it as an Nx monorepo on Next.js 11 with shared UI libraries for the team.
- Delivered production iOS and API changes with AI coding agents inside a verification process I designed: automated gates, contract tests, and staged multi-reviewer code review.
Technologies: React, Next.js, TypeScript, Redux, Nx, Node.js, NestJS, Prisma, MySQL, iOS, Swift, Xcode, Fastlane, GitHub Actions, Docker, REST APIs, Performance Optimization, APIs, Amazon Web Services (AWS), Android, Apollo, Apollo Client, Continuous Integration (CI), Contract Testing, Figma, Front-end Architecture, Full-stack, JSON Web Tokens (JWT), JavaScript, Jest, Large Language Model Operations (LLMOps), Mobile, Mobile Web, Monorepos, OpenAPI, Performance Testing, Push Notifications, Python, React Native, Redux Toolkit, RxJS, Server-side Rendering (SSR), Software Architecture, Test-driven Development (TDD), Unit Testing, User Interface (UI), Webpack, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Large Language Models (LLMs), AI Agents, Code Review, Code Auditing, Startups, Vercel, Architecture, Authentication, Authorization, Git
Senior Developer
2023 - 2023
Silver Eagle Systems LLC
- Built the Angular admin console for Thulium, a VMware vCenter administration plugin, as an Nx monorepo of 20 feature libraries for hosts, virtual machines, vCenters, contacts, and metadata.
- Implemented state management and API caching with NgRx and RTK Query, delivering full CRUD for hosts, virtual machines, contacts, and metadata types.
- Built the vCenter plugin-registration wizard, the authentication flow with route guards, and idle and session timeouts with automatic logout.
- Built the UI on VMware's Clarity design system, including drag-and-drop sortable lists and paginated contact management.
- Set up GitHub Actions CI and the release bundle that ships the admin UI, user UI, and REST API together behind an NGINX reverse proxy.
- Upgraded the admin and user interfaces to Angular 14 and Nx 15.
Technologies: Angular, JavaScript, CSS, MySQL, Python, TypeScript, NgRx, RxJS, Redux, Nx, GitHub Actions, NGINX, CircleCI, VMware, APIs, Continuous Integration (CI), Front-end Architecture, Full-stack, JSON Web Tokens (JWT), Jest, Monorepos, REST APIs, Test-driven Development (TDD), Unit Testing, User Interface (UI), Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, SCSS, Model View ViewModel (MVVM), Code Review, Startups, Git
Front-end Developer
2022 - 2022
Hotel Reservations Company
- Fixed booking-date consistency in a Next.js hotel reservation site so that changing dates forces a fresh rate search before a guest can book.
- Refactored booking state into a shared React context and cleaned up duplicate search-form components in a Next.js/TypeScript codebase.
- Made search results refresh correctly in the single-page app and showed nightly rates only when the selected dates had been searched.
- Upgraded Next.js and Mongoose through Snyk-flagged dependency updates and added API documentation tooling.
Technologies: React, TypeScript, Jest, Next.js, Redux, Node.js, NGINX, Webpack, MongoDB, Mongoose, Google Maps API, Styled-components, APIs, Amazon Web Services (AWS), JavaScript, Mobile, NoSQL, OpenAPI, REST APIs, React Hook Form, RxJS, Server-side Rendering (SSR), Test-driven Development (TDD), Unit Testing, Web Performance Optimization (WPO), Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Redux Thunk, Code Review, Startups, Vercel, Authentication, Authorization, Webhooks, Git
Developer
2021 - 2021
GrowthDeFi
- Built a subgraph with a GraphQL schema indexing token supply, reserves, daily prices, and total value locked for a DeFi protocol on the Ethereum mainnet and Kovan.
- Developed the React and Redux-Saga dApp front end, connecting wallets through web3-react, WalletConnect, and WalletLink, charting protocol metrics.
- Started the Nx, Next.js, and TypeScript front end for RAAVE, a companion DeFi product, with styled-components and Cypress tests.
Technologies: React, Web3.js, GraphQL, Solidity, TypeScript, Jest, Next.js, Redux, Node.js, NGINX, Webpack, Shell Scripting, Nx, Redux-Saga, Ethers.js, Blockchain, CircleCI, Docker, APIs, JavaScript, Monorepos, REST APIs, Test-driven Development (TDD), Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Startups, Git
Senior Front-end Engineer
2020 - 2021
Verb Technology Inc.
- Migrated legacy PHP API endpoints to Node.js serverless functions on AWS Lambda, routing each endpoint to new or legacy code during a gradual cutover.
- Built parity tests that compared migrated endpoints against snapshots of the legacy API using Mocha, Chai, Postman, and Newman.
- Developed features in an Nx/Angular front-end monorepo with server-side rendering, Jest and Cypress tests, and automated pull-request checks.
Technologies: Angular, Jest, Node.js, Test-driven Development (TDD), AWS Lambda, Serverless Framework, Sequelize, MySQL, Mocha, Postman, Nx, TypeScript, Cypress, Sentry, APIs, Amazon Web Services (AWS), Chai, Event-driven Architecture, Figma, Front-end Architecture, Full-stack, JavaScript, Mobile, Mobile Web, Webpack Module Federation, Monorepos, Push Notifications, REST APIs, Redux Toolkit, RxJS, Server-side Rendering (SSR), Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, Model View ViewModel (MVVM), JSON, CSS3, HTML5, SCSS, Code Review, Startups, Authorization, Git
Senior Software Engineer and Architect
2017 - 2021
Rally Health
- Scaffolded the Angular and Redux-Saga clinician dashboard in 2017 and remained its top committer through upgrades to Angular 5, 8, 9, and 10.
- Implemented Angular Universal SSR with the Redux store serialized into the page and rehydrated in the browser; with differential loading, cut initial page load by over 70% and route changes by around 65%.
- Built an injectable config factory that reads window in the browser and process.env on the server, so one bundle ran under SSR with runtime configuration.
- Added differential serving to the Express SSR server, sending an ES5 build to IE11 and ES2015 modules to modern browsers.
- Clustered the Node SSR server and hardened it with Helmet, a nonce-based Content Security Policy, and server-side token authentication.
- Moved batch data loading and search indexing into a Web Worker orchestrated by Redux-Saga, keeping the dashboard responsive on large patient-program lists.
- Wrote and published two TypeScript Redux libraries bridging the Layer and Sendbird chat SDKs, giving the dashboard one Redux source of truth for real-time messaging.
- Built CI/CD with CircleCI and Docker build images, test-gated semantic releases, Storybook publishing, and CloudFront cache invalidation and New Relic SPA monitoring.
- Coached two other product teams through adopting server-side rendering, and both shipped it.
- Led Recover's rebuild from Angular to Next.js, relaunching the platform as OnePass (continued under UnitedHealthcare/Optum).
Technologies: Angular, TypeScript, Redux, Redux-Saga, Server-side Rendering (SSR), Node.js, Express.js, HTML5 Web Workers, SendBird, Jest, Storybook, Docker, CircleCI, Performance Optimization, APIs, Amazon CloudFront, Amazon Web Services (AWS), Android, Angular Universal, Apollo, Apollo Client, GraphQL Federation, Continuous Integration (CI), Datadog, ECMAScript (ES6), Event-driven Architecture, Figma, Front-end Architecture, GraphQL, JavaScript, Mobile, Webpack Module Federation, Monorepos, Multithreading, NPM, New Relic, Next.js, OpenAPI, Push Notifications, Python, REST APIs, React, React Native, RxJS, Software Architecture, Unit Testing, Web Performance Optimization (WPO), Webpack, Website Performance, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, Model View ViewModel (MVVM), JSON, CSS3, HTML5, SCSS, Redux Thunk, Apache HTTP Server, Code Review, Code Auditing, Architecture, Authentication, Authorization, HIPAA, Webhooks, Git
Front-end Architect
2020 - 2020
Costco Wholesale
- Designed the front-end architecture for a jewelry image-catalog PWA: normalized state, cached query results, and pagination that stays consistent while records change.
- Specified a two-phase search that returns Cosmos DB results immediately, then fills in slower IBM iSeries inventory data from a second endpoint.
- Documented the search data flow between the React PWA, Cosmos DB, and IBM iSeries as a PlantUML sequence diagram for the team.
Technologies: React, TypeScript, Progressive Web Applications (PWAs), Material UI, Storybook, Jest, React Testing Library, Azure Cosmos DB, APIs, Figma, Front-end Architecture, JavaScript, Node.js, REST APIs, Software Architecture, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Code Review, Architecture, Git
Senior React Developer
2017 - 2017
Libre Technology, Inc.
- Built DocuPop's React/Redux client from scratch, including a multi-step onboarding flow with redux-form and Material-UI, then deployed it to Heroku.
- Created and published a shared npm package of Joi validation schemas so the React client and Node API enforced identical rules for SSN, DOB, and FSA credentials.
- Implemented token-based auth in the client with a typed fetch wrapper, bearer headers, structured API errors, and sessions persisted via redux-persist and localForage.
- Set up Flow typing, Jest/Enzyme tests with fetch-mock and redux-mock-store, CircleCI, and Codecov coverage reporting within the first two weeks.
- Extended Create React App through react-app-rewired so the browser used Joi-browser, letting one validation library run on client and server.
Technologies: React, REST APIs, Git, Gulp, Webpack, Heroku, Salesforce, Redux, Redux Form, Material UI, FlowType.JS, Jest, Enzyme, Joi, NPM, CircleCI, Heroku Connect, APIs, JavaScript, Redux Persist, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Startups
Senior UI Engineer
2017 - 2017
MedChat, LLC
- Rewrote an embeddable patient-chat widget in React, reorganizing Redux into feature modules with redux-saga business logic and custom WebSocket middleware.
- Made real-time chat resilient with automatic socket reconnect, message queueing, and saga race/timeout logic so chats end cleanly when agents or connections drop.
- Added JWT expiry detection and token refresh with jwt-decode and redux-persist expiry transforms, so expired patient sessions were detected and refreshed.
- Fixed an XSS vulnerability in chat messages by sanitizing message text with xss-filters and hardening auto-linkified URLs.
- Cut API load from embedded widgets by removing polling and fetching agent availability only on expand, with call-count-bounded saga tests.
- Built a Jest test suite for the chat lifecycle, login, topics, and widget modules using redux-saga-test-plan, with CI and Coveralls coverage reporting.
- Created a JavaScript embed API (programmatic launch, hidden trigger, feature flags) and auto-contrast theming so customers could brand and control the widget.
- Built an Angular/NgRx drag-and-drop form builder with a draft ("shadow") editing model, with nearly 1,000 lines of reducer specs.
Technologies: CSS, JavaScript, HTML, React, Redux, Redux-Saga, WebSockets, JSON Web Tokens (JWT), Jest, Angular, NgRx, Web Security, HIPAA Compliance, APIs, Mobile, Mobile Web, Next.js, Node.js, Redux Persist, RxJS, Software Architecture, TypeScript, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, Model View ViewModel (MVVM), JSON, CSS3, HTML5, SCSS, Redux Thunk, Apache HTTP Server, Code Review, Startups, Authentication, Authorization, HIPAA, Webhooks, Git
Architect and Lead Developer
2016 - 2017
NOTATE!
- Architected NOTATE!, a React/Redux web app for authoring and auto-grading music-notation exercises, and wrote the project plan and data model.
- Modeled musical notation in Redux state after Humdrum **kern (questions, staves, layers, spines, measures) so student answers can be compared to keys.
- Set up the front-end foundation: Flow types, Immutable.js, redux-saga, feature-module structure, Jest, ESLint, CircleCI, and Codecov.
- Scaffolded the Express/MongoDB API on Heroku, then directed a contract developer who built the assignment and document endpoints and UI.
Technologies: React, Redux, Redux-Saga, Immutable.js, FlowType.JS, Jest, Node.js, Express.js, MongoDB, Mongoose, Architecture, APIs, Front-end Architecture, JavaScript, Mobile, Next.js, NoSQL, Software Architecture, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, SCSS, Redux Thunk, Apache HTTP Server, Startups, Vercel, Git
React and Redux Front-end Developer
2016 - 2017
fuboTV
- Built the live TV program guide (EPG) in React/Redux for web and mobile: playable airings, a 6-hour timeline aligned to the hour, and hover previews.
- Created a reusable redux-observable epic factory (RxJS switchMap/takeUntil for cancellation) plus an RxJS marble-test helper, and used them for async API calls.
- Implemented the DVR recordings experience: record/cancel/delete dialogs, a DVR-full modal, and Redux epics, reducers, and selectors with Jest coverage.
- Built SEO-ready channel detail pages with slug routing, react-helmet canonical URLs, and prerender.io 404 status codes for a client-rendered React SPA.
- Added subscription-aware access control to channel pages, handling logged-out, active, and expired subscribers through a credential reducer and modal flow.
- Extended the shared npm API client with public and authenticated guide, channel, and network endpoints, response mappers, and nock-backed tests.
- Built TV home content modules (popular-series carousel, promoted content, A–Z series filter) with Immutable.js and memoized reselect selectors.
Technologies: FlowType.JS, Webpack, Jest, RxJS, Redux, React, JavaScript, User Experience (UX), User Interface (UI), Redux-observable, Reselect, Immutable.js, Enzyme, Search Engine Optimization (SEO), REST APIs, APIs, Mobile, NPM, Node.js, Server-side Rendering (SSR), TypeScript, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Code Review
Senior Full-stack Developer
2016 - 2016
HP Enterprise
- Built HPE Gaia's account-management service end to end in Node.js/Express and PostgreSQL across the API, database, and SPA.
- Implemented Google OAuth 2.0 sign-in with Passport, issuing JWTs in httpOnly cookies and enforcing role-based access (superuser, admin, analyst) on API routes and UI.
- Designed the relational schema with Knex migrations and Bookshelf models, moving cascading deletes and invitation integrity into PostgreSQL constraints.
- Wrote the REST API contract-first in API Blueprint, verified it with Dredd contract tests and Mocha/Supertest suites, and published HTML docs with Aglio.
- Built a user-invitation workflow with UUID tokens, revocation, acceptance screens, and templated invitation emails sent via Express and Pug.
- Developed the admin SPA in ES6 AngularJS 1.5 with Webpack, UI-Router, and Karma, including permission-aware routing and a centralized error interceptor.
- Containerized the app with Docker Compose (Node.js, Angular client, PostgreSQL) with DB health checks, automatic seeding, and CircleCI builds.
- Created a versatile account management application for deployment across multiple HP properties.
- Created an Express-based API layer with support for multiple user roles.
- Designed an approach to integrating the account management application into Kibana.
Technologies: AngularJS, Back-end, Kibana, Node.js, Express.js, PostgreSQL, Knex.js, Bookshelf.js, Passport.js, JSON Web Tokens (JWT), Webpack, Mocha, Dredd, Docker, CircleCI, APIs, Contract Testing, ECMAScript (ES6), Elasticsearch, JavaScript, REST APIs, Role-based Access Control (RBAC), Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, Model View ViewModel (MVVM), JSON, CSS3, HTML5, Authentication, Git
Full-stack Development Lead and UX Specialist
2016 - 2016
BetaSmartz
- Created customizable and reusable React/Redux components for a robo-advisor investing platform.
- Implemented a test-driven development workflow with Enzyme for the React front end.
- Streamlined delivery with an Agile workflow focused on small, incremental, reliably tested releases.
Technologies: D3.js, NumPy, Python, Django, Enzyme, Ramda, Redux, React, JavaScript, API Integration, User Experience (UX), Full-stack, User Interface (UI), UX Design, Test-driven Development (TDD), APIs, Agile Software Development, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, JSON, CSS3, HTML5, Selenium, Code Review, Startups, Vercel, Git
Senior Developer
2014 - 2015
Cengage Learning
- Found the cause of slow page loads by benchmarking the legacy content adapter: 1,153 milliseconds to first byte versus 98 milliseconds direct, degrading to about 15 seconds under load.
- Built latency and load-testing scripts that ran 1,141 parallel requests and turned the results into a report that guided the fix.
- Built key-term flashcard generation for Cengage's 4LTR Online study app, turning chapter-review data into study decks from a single button in AngularJS.
- Replaced a third-party calendar with a custom AngularJS directive that supports drag-and-drop scheduling, save-on-drop, and deletion of student assignments.
- Improved rendering of the studyboard tile grid by memoizing tile computations, adding one-time bindings and debouncing, and cutting redundant watchers.
- Refactored the assignments section into an Assignment factory, route resolves, and a chapter/topic accordion directive backed by new Express API routes.
- Fixed iOS 7 note-taking bugs with a tested iOS-version detection service and touch-scroll handling, and added FastClick for mobile tap response.
Technologies: AngularJS, Express.js, Node.js, API Integration, User Experience (UX), User Interface (UI), UX Design, JavaScript, Sass, Grunt, Karma, Mocha, Jenkins, Mobile Web, Performance Optimization, Performance Testing, APIs, Unit Testing, Xcode, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, jQuery, Model View ViewModel (MVVM), JSON, CSS3, HTML5, SCSS, Selenium, Code Review, Git
Mobile Application Architect | Lead Developer
2013 - 2014
Morgan Stanley
- Architected the front end for the company's flagship banking app.
- Built core features of Morgan Stanley Wealth Management's hybrid iOS/Android client app in AngularJS and Cordova: portfolio activity, holdings, account selector, and alerts.
- Designed the app-wide HTTP interceptor and notification service that standardized error, timeout, and offline messages and suppressed duplicate alerts.
- Added offline and timeout resilience: requests were rejected when the device was offline, timeouts became resolvable promises, and failures showed clear recovery messages.
- Taught the development team how to implement useful units and perform automated testing.
- Cut redundant network calls by adding angular-cache response caching with normalized keys and client-side caching of recent portfolio searches.
- Built a reusable bar-chart directive for portfolio holdings and a searchable, grouped account selector used across the app's screens.
- Refactored the monolithic AppModel into a SettingsFactory, separating request configuration from app state to simplify timeout handling.
- Improved team tooling with Grunt template compression, ngdocs, API proxying, a JSHint pre-commit hook, and scripts to pre-prime the native shell.
- Delivered a high-use, cross-platform banking app that processed billions of dollars in transactions without error, and worked across the AngularJS client and the .NET services behind it to integrate portfolio, holdings, and alert data.
Technologies: .NET, AngularJS, API Integration, User Experience (UX), Full-stack, User Interface (UI), UX Design, JavaScript, Cordova, iOS, Android, Sass, Grunt, Karma, Jasmine, Mobile, APIs, PhoneGap, Protractor, Unit Testing, Xcode, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, Model View ViewModel (MVVM), JSON, CSS3, HTML5, SCSS, Selenium, Code Review, Code Auditing, Architecture, Software Architecture, Authentication, Authorization, Git
Senior UI Developer
2013 - 2013
Beche Group, LLC
- Developed a custom implementation of Ext JS drag-and-drop that worked on desktop and mobile.
- Created a high-performance user interface that rendered in under 100 milliseconds.
- Worked through fintech and security concerns for best practices implementation.
Technologies: Ext JS, API Integration, User Experience (UX), UX Design, JavaScript, Sencha Touch, Code Review, Git
Senior Developer
2012 - 2012
Foreclosure Radar
- Developed a responsive desktop/mobile site with high performance across Maps APIs.
- Created a custom hybrid loading scheme for top performance on different platforms.
- Taught best practices to the development team regarding mobile web.
Technologies: Ext JS, Sencha Touch, User Experience (UX), Full-stack, User Interface (UI), UX Design, JavaScript, Selenium, Code Review, Startups
Application Architect | Senior Developer
2011 - 2012
Morgan Stanley
- Built client-financials screens (balances, positions, activity, account plating) for an iPad wealth-management app used by Morgan Stanley financial advisors.
- Designed a request-synchronization layer (SyncDirector) that batched data requests from nested controllers and refreshed every view with a single broadcast.
- Implemented server-side sorting for data grids, plus buffered-grid and orientation-handling plugins that extended Sencha Touch for large datasets on iPad.
- Integrated the mobile front end with SOAP/XML web services (WCF), including client typeahead search and household/account-group data.
- Mapped the app's controller architecture and testable components, then planned the migration from Sencha Touch 1 to Sencha Touch 2.
Technologies: Sencha Touch, API Integration, User Experience (UX), Full-stack, User Interface (UI), UX Design, Ext JS, JavaScript, Mobile Web, iOS, Tablet UI, SOAP, Model View Controller (MVC), APIs, Unit Testing, Xcode, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, jQuery, JSON, CSS3, HTML5, Selenium, Code Review, Code Auditing, Architecture, Software Architecture, Authorization
Lead Developer | Application Architect
2006 - 2011
Warner Bros.
- Led the development of an internal management system using Ext JS.
- Developed dozens of sites with Adobe Flash/ActionScript 3.
- Built and maintained more than 80 sites, including Warner Bros.' international asset-delivery system.
Technologies: Oracle, CodeIgniter, PHP, Flex, Flash, Ext JS, User Experience (UX), Full-stack, User Interface (UI), UX Design, APIs, Adobe Photoshop, JavaScript, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, Agile, Scrum, Jira, jQuery, JSON, CSS3, HTML5, Apache HTTP Server, Selenium, Code Review, Code Auditing, Architecture, Software Architecture, Authorization
Developer
2003 - 2006
University of Chicago
- Converted storyboards into fully functional websites.
- Developed, from end-to-end, work sites with ColdFusion and SQL Server.
- Implemented PHP performance optimization across multiple sites and created new PHP sites end-to-end.
Technologies: Microsoft SQL Server, PHP, Perl, Adobe ColdFusion, User Experience (UX), Full-stack, User Interface (UI), Adobe Photoshop, APIs, JavaScript, Unit Testing, Functional Testing, Behavior-driven Development (BDD), Agile Software Testing, jQuery, JSON, CSS3, HTML5, Code Review, Code Auditing, Software Architecture, Authorization
Experience
Per-tier Next.js Caching for 5 Million Users
For a leading fitness-benefit app, I had to serve personalized pages to about 5 million members across roughly 100 membership tiers without rendering every page on every request. I built it on Next.js, Apollo Client, and a GraphQL edge service I designed. During server rendering, the app walked the React component tree to collect every GraphQL query (Apollo getDataFromTree), pre-rendered one page per membership tier with incremental static regeneration, and rehydrated the Apollo cache in the browser so pages became interactive without refetching. A request intercept used each member's secure session cookie to route them to their tier's cached page. Average LCP settled at about 0.5 seconds, 80% faster than the company's 2024 goal, with low server load. Next.js has since built a similar approach in the form of Partial Prerendering.
Federated React Native Platform with GraphQL Subgraphs
A flagship Optum app needed a mobile platform that many product teams could build on at the same time. I architected that platform and built its core. On the client, I built federated React Native code: feature bundles developed and shipped independently, then loaded into a host app at runtime. I started from Re.Pack's module federation and built a loading system of my own on top of it. On the server, I built the GraphQL layer as a federation of Node.js subgraphs, so each team owned its part of the schema, and the app queried the single graph through Apollo Client. I also built the shared mobile components that feature teams used on iOS and Android. With that architecture in place, teams shipped features quickly on both platforms. Details of the loading and federation design are proprietary.
Gym Search at Scale: Geo-tiled GraphQL Queries
A fitness-benefit app for about 5 million members was designed around 100–300 gyms within 40 miles of a member; in populated areas, the real figure was 1,200+ gyms and far more classes. I replaced the single large query with a grid of small squares fetched closest-first, adding day-by-day segments for classes. Each square got its own Apollo cache key, so panning or widening the radius reused data already loaded, and BatchHttpLink merged requests into fewer HTTP calls. I also proposed snapping search centers to a grid so nearby members made identical, cacheable requests. The team carried the idea into fixed 0.1° geo-tiles and a knownTileKeys argument on the GraphQL edge.
Enterprise AI Adoption: Moving Hundreds of Developers to AI-assisted Engineering
At a Fortune 5 health company, I moved hundreds of developers to AI-assisted engineering. I built the enablement program end to end: the training tooling, hands-on materials, and a series of talks that showed developers what GitHub Copilot and Claude could do in their own work. I also introduced AI tooling that made it easier to find information across the organization's large body of engineering documentation. I organized and spoke at an internal AI conference with more than 800 attendees. Hundreds of developers adopted AI-assisted workflows as a result.
Gated AI-assisted Delivery for a Production App and API
For a music-education company, I shipped production changes to a native iOS app and its NestJS API with AI coding agents working inside a verification process I designed. Agents plan and implement small, reviewable slices, but nothing merges on an agent's say-so. Every change must pass custom automated gates: 820 unit tests, 365 API contract tests, performance baselines, type checks, and ten CI gates on the iOS app. Each change then goes through a staged code review in which independent parallel reviewers raise findings, and every finding is re-verified against the source before it's acted on. The process delivered a versioned API migration and a production latency fix (sign-in from 4 seconds to 51 milliseconds) with a full evidence trail. I also cut the process's own overhead after measuring where agent effort went. Details of the gates and review design are proprietary.
API Latency: 4-second Sign-in to 51 Milliseconds
A music-education company's iOS app took 3 to 4 seconds to sign users in. I traced the latency to the back end's database traffic: every query crossed a public network proxy at about 145 milliseconds per round trip, and one sign-in lookup scanned 137,499 rows. I moved the Node.js (NestJS) service onto private networking next to the MySQL database and added the missing indexes, so the lookup now reads 2 rows. Sign-in dropped to 51 milliseconds, and catalog reads from 715 milliseconds to 4 milliseconds. The work shipped behind a versioned API, 820 unit tests, and 365 contract tests, with a documented rollback plan.
Rescuing a Launch: 20-second P95 to 2 Seconds with Web Workers
Two weeks before the site launched, production data arrived 100x larger than the spec: 20,000 items instead of 200. The browser built an in-memory index of every item on the main thread, so pages froze, garbage collection stalled, and P95 load time passed 20 seconds before the app crashed. With no time for a rewrite, I moved the processing onto Web Workers and split the data into small parallel requests, freeing the main thread. P95 dropped to about 2 seconds with 100% of the data, and the site launched on time. After launch, I refactored Apollo Client's cache read and merge logic, which made the data-heavy pages almost 10x faster again.
Event-driven Architecture and Push Notifications for a Flagship UHC App
A flagship UHC app runs on React Native, and every change was built and tested on both iOS and Android. I designed and wrote the eventing engine behind the app's push notifications. It is a TypeScript, event-driven platform built on RxJS that brings Kafka-style event streaming to JavaScript applications on mobile and web. Customer satisfaction in the app rose, and push notifications contributed to that. The platform was then adopted by several other UnitedHealth Group products, and its design guided the build-out of a later flagship Optum app. Details of the event model are proprietary.
Server-side Rendering for a Healthcare Dashboard: 70% Faster Initial Load
A healthcare provider dashboard I led was a large Angular and Redux single-page app that had to render quickly while still supporting IE11. I added Angular Universal server-side rendering. The Express server prefetches public data, builds the initial Redux state, and injects it into the page with a CSP nonce, so the client store rehydrates instead of starting empty. I built an injectable config factory that reads window in the browser and process.env on the server, clustered the Node.js server, hardened it with Helmet and a Content Security Policy, and served an ES5 build only to IE11 while modern browsers got ES2015 modules. With bundle-size work, average initial page load fell by more than 70% and route changes by about 65%, and two other product teams adopted SSR with my guidance.
Talk: Performance-oriented Architecture for Large Front-end Teams (XtremeJS 2021)
https://xtremejs.dev/2021/schedule/A conference talk on keeping large enterprise front ends fast when many developers of different experience levels share one codebase. It introduces my bridging-façade pattern, where one module acts both as the bridge between the data store and the UI components and as a façade over the store. That keeps components simple and protects page-load and rendering performance as requirements change. The pattern came from my work at UnitedHealthcare and was used in production on OnePass.
React Storefront and Next.js Migration for a Music Education Platform
A music-education company that sells piano play-along tracks needed a modern web storefront to replace its legacy PHP site. I built a React and TypeScript single-page app with a Redux store using redux-query and normalizr for API entities, typed models for shows, categories, and tracks, and a browse page and home page with category and top-ten carousels. When search visibility and first-load speed became priorities, I moved the app from Create React App to Next.js with file-based pages and a connected-next-router bridge that kept Redux routing working. I then restructured the front end as an Nx monorepo on Next.js 11 and React 17 with shared UI libraries, which gave the team a clean base to build and deploy from.
Thulium: Angular Admin Console for a VMware vCenter Plugin
Silver Eagle Systems needed an admin console for Thulium, its VMware vCenter administration plugin. I built nearly all of it in Angular and TypeScript as an Nx monorepo of 20 feature libraries covering hosts, virtual machines, vCenter registration, contacts, and configurable metadata types. I used NgRx with RTK Query for state and API caching, which gave every entity full create, read, update, and delete support with consistent loading and error handling. I also built the plugin-registration wizard, authentication with route guards, and idle and session timeouts with automatic logout, all on VMware's Clarity design system. I set up GitHub Actions CI and the release bundle that ships the admin UI, user UI, and REST API together behind an NGINX reverse proxy.
Live TV Program Guide for FuboTV
fuboTV's new React web app needed a live program guide where viewers could scan what was airing across channels and start watching immediately, on both desktop and mobile. I built the Episode Guide end to end. On the data side, I added a guide endpoint and response mapper to the shared API client library. On the web side, I built redux-observable epics, an Immutable.js-backed reducer and selectors, and React components for the channel rows, header, and timeline. The timeline opens at the top of the current hour, shows a six-hour window, marks airings as playable, and opens the channel player from the guide. The guide shipped through several merged PRs, with reducer and component tests written in Jest alongside the code.
Real-time Patient Chat Widget (Embeddable React App)
A healthcare messaging company's embeddable chat widget sits on providers' websites so patients can message staff, and it has to stay reliable on any network. I led its rewrite in React, reorganizing Redux into feature modules with redux-saga handling the business logic and a custom WebSocket middleware that queues outgoing messages. I added automatic reconnect when the socket drops. I also added saga race and timeout logic so chats end cleanly even if the server confirmation never arrives, plus JWT expiry detection and refresh, conversation persistence with redux-persist, and sanitization of message text. For host sites, I built a small JavaScript API (programmatic launch, hidden trigger) and automatic text contrast against each customer's brand color. I wrote a Jest test suite covering the chat lifecycle, and the rewrite became the production widget.
Account and Access Management Service for HPE
HPE's Gaia platform needed a way to manage customer accounts, their users, and what each user could do. I built the service from an empty repository in about eight weeks and wrote nearly every commit. On the back end, I designed a PostgreSQL schema with Knex migrations and Bookshelf models for users, accounts, roles, and invitations, with integrity rules such as cascading deletes enforced in the database. Users sign in with Google OAuth 2.0 through Passport, the API issues a JWT in an httpOnly cookie, and middleware enforces superuser, admin, analyst, and self-only permissions. I wrote the API contract-first in API Blueprint and ran Dredd against it so the docs and implementation couldn't drift. The ES6 AngularJS client hides actions a user isn't allowed to take, and the service ships as Docker Compose with a seeded, health-checked Postgres and CircleCI builds.
Redux Bridges for Real-time Chat SDKs (Layer and Sendbird)
Provider-to-patient and provider-to-provider messaging depended on third-party chat SDKs. Those SDKs manage their own state, so keeping them consistent and testable alongside our Redux store called for a dedicated layer. I wrote and published two TypeScript libraries. The first bridged the Layer XDK to Redux, with typed models for conversations, messages, queries, and typing indicators, plus read receipts, automatic pagination, notifications, and memoized selectors. After the platform moved to Sendbird, I built most of a Redux-Saga-based Sendbird library: I refactored its messaging, added channel previews and message de-duplication, made it safe for server-side rendering, and added custom message types. Both were published to the company registry through CI. The dashboard got a single Redux source of truth for chat.
Advanced Language Engine with Vector Similarity Search
Spelling-based language engines that fail on English words like "cough" and "though" need to be handled instead at the phonetic level. A Python pipeline extracts each word's pronunciation in the International Phonetic Alphabet from Wiktionary, and ends up with an advanced language engine, the details of which are proprietary (but the software design is challenging and interesting).
Resilient Networking Layer for a Wealth Management Mobile App
A wealth-management firm's hybrid mobile app (AngularJS in a native Cordova shell) had to behave well on unreliable mobile networks. I owned the networking layer. I built an HTTP interceptor and NotificationService that route every error, timeout, and "no connection" state through one place and suppress duplicate messages. Requests are rejected up front when the device is offline, timeouts are resolvable promises, so spinners always clear, and there is a network-status directive. I added angular-cache response caching with normalized keys (per-request IDs stripped), so moving between screens didn't re-fetch data. I also split request settings out of the AppModel into a SettingsFactory. Error handling across feedback, alerts, and generic failures now follows one consistent pattern.
iPad Wealth Management App for Financial Advisors
Morgan Stanley financial advisors needed their clients' balances, positions, and activity on an iPad, served from existing SOAP services built for desktop. Working through the agency Momentum, I built the client-financials module of the Sencha Touch web app: balances, positions, activity, and account "plating" views, plus client search with typeahead. Dense screens had many nested components that each needed their own data, so I designed a synchronization layer that queued those requests, sent them together once every controller was ready, and refreshed all views with one broadcast. I also added server-side grid sorting and buffered-grid and orientation plugins. When Sencha Touch 2 arrived, I wrote the controller map and migration plan.
Finding a 12x Latency Penalty in a Legacy Content Adapter
A textbook publisher's online study app delivered content through a legacy adapter layer, and I was asked to find where time was going. I wrote shell scripts that fetched 200 images 25 times each, both directly and through the adapter, and logged time to the first byte. Direct requests averaged 98 milliseconds; adapter requests averaged 1,153 milliseconds. Under a parallel load test of 1,141 requests, the adapter degraded to about 15 seconds by the final image while the direct path held steady. I wrote up the results in a report that located the slowdown in the adapter and guided the fix.
Book in Progress: Computer-assisted Music Research
I'm writing a book on computer-assisted music research. It teaches modern JavaScript through real problems from musical set theory, such as computing the normal form of a pitch-class set: the most compact ordering of a set of notes, and the basis for comparing chords and melodic figures. One chapter is devoted to test-driven development, working through the algorithm's tricky cases, such as ties between equally compact orderings, test by test. The book draws on my PhD in mathematical music theory.
Education
2003 - 2010
PhD in Music Theory
University of Chicago - Chicago, IL, USA
2001 - 2003
Master of Arts Degree in Music Theory
University of Chicago - Chicago, IL, USA
1997 - 2001
Bachelor of Arts Degree with Honors in Music
Columbia College in the City of New York (Columbia University) - New York, NY (USA)
Skills
Libraries/APIs
Redux-Saga, Lodash, Chai, React, Node.js, jQuery, REST APIs, NgRx, RxJS, NumPy, SciPy, Bookshelf.js, Ramda, D3.js, FlowType.JS, Passport.js, HTML5 Web Workers, SendBird, Web3.js, Google Maps API, React Testing Library, Redux Form, Immutable.js, Reselect, Apollo Client, OpenAPI, React Hook Form, Redux Persist
Tools
Redux Thunk, Karma, NPM, Jira, Flash, Adobe Photoshop, Grunt, Mocha, Git, Apache HTTP Server, Gulp, Mongoose, TanStack Router, Kibana, CircleCI, Knex.js, Webpack, NGINX, Xcode, Figma, AI SDK, Claude, Nx, Prisma, Fastlane, VMware, Sequelize, Postman, Sentry, Jenkins, Angular Universal, Create React App, Redux Toolkit, Amazon CloudFront, Webpack Module Federation, GitHub Copilot
Languages
GraphQL, TypeScript, CSS3, CSS, XHTML, HTML, HTML5, SCSS, Sass, PHP, ECMAScript (ES6), JavaScript, Python, Perl, Swift, Solidity, SQL, API Blueprint, Bash
Frameworks
Next.js, Redux, Angular, JSON Web Tokens (JWT), PhoneGap, Jest, Ext JS, Sencha Touch, Jasmine, Express.js, AngularJS, React Native, Selenium, CodeIgniter, NestJS, .NET, Dredd, Django, Flex, Serverless Framework, Cypress, Material UI, Protractor
Paradigms
Model View ViewModel (MVVM), Model View Controller (MVC), Unit Testing, Functional Testing, Behavior-driven Development (BDD), Test-driven Development (TDD), Scrum, Agile Software Development, Agile, HIPAA Compliance, UX Design, Test Automation, Microfrontends, Search Engine Optimization (SEO), Automated Testing, Continuous Integration (CI), Load Testing, Design Patterns, Event-driven Architecture, Web Performance Optimization (WPO), Role-based Access Control (RBAC)
Platforms
iOS, Android, Amazon Web Services (AWS), Vercel, Adobe ColdFusion, Oracle, Docker, Blockchain, AWS Lambda, Heroku, Salesforce, Mobile, Mapbox, New Relic
Storage
JSON, MySQL, PostgreSQL, NoSQL, Microsoft SQL Server, MongoDB, Data Pipelines, Redis, IndexedDB, Azure Cosmos DB, Datadog, Elasticsearch
Other
Agile Software Testing, Cordova, APIs, Architecture, API Integration, User Experience (UX), Full-stack, User Interface (UI), Large Language Models (LLMs), Software Architecture, Code Review, Code Auditing, Authentication, Authorization, HIPAA, Shell Scripting, Vite, Large Language Model Operations (LLMOps), Startups, Webhooks, Enzyme, Music, AI Agents, GitHub Actions, Pgvector, Vector Databases, Natural Language Processing (NLP), Apollo, Server-side Rendering (SSR), Storybook, Performance Optimization, Styled-components, Ethers.js, Progressive Web Applications (PWAs), WebSockets, Web Security, Joi, Heroku Connect, Back-end, Redux-observable, Mobile Web, Performance Testing, Tablet UI, SOAP, Core Web Vitals, Caching, Website Performance, Multithreading, Geolocation, Database Optimization, Railway, Video Streaming, OAuth, iPad, Public Speaking, Front-end Architecture, Algorithms, GraphQL Federation, Monorepos, Push Notifications, Contract Testing, Prompt Engineering, AI Integration, Technical Leadership, Technical Training
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