Mark Fayngersh
  • Writing
  • Work
  • Photos
  • Books
  • svelte-check-rs

    Jan 2026

    Drop-in replacement for svelte-check written in Rust. 10-100x faster through parallel processing, with full feature parity.

  • Claude Agent Desktop

    Nov 2025

    Desktop app wrapping the Claude Agent SDK with bundled runtimes, pre-configured skills for document handling and data analysis, and shared workspaces.

  • Narrative

    Jan 2025

    AI agents for compliance, risk, and fraud operations at banks and fintech companies.

  • Careswitch App

    Mar 2024

    HIPAA-compliant iOS app for shift management and care documentation. Supports offline sync, adjustable text sizes, and high-contrast modes.

  • Careswitch AI Assistant

    Aug 2023

    Copilot with agentic tool calling, real-time data retrieval, file upload analysis, and dynamic chart generation.

  • Careswitch

    May 2017

    Co-founded modern EHR for home care agencies. Scheduling, billing, compliance, and a caregiver marketplace. Backed by Khosla Ventures.

  • Quartet Health Data Platform

    Oct 2015

    Behavioral health data platform using Datomic for immutable, fact-based storage. EDN-based query API with time-travel queries, data versioning, and property-based testing via spec generators.

  • CrowdTwist Loyalty Platform

    Sep 2012

    White-label loyalty platform for brands like L'Oréal and Pepsi. Migrated from PHP to Backbone.js SPA, then rebuilt with Angular.js and Webpack. Acquired by Oracle in 2019.

  • MIT Media Lab - ROAR

    Sep 2011

    Second-screen app using audio fingerprinting to sync with live TV broadcasts. Groups viewers into virtual stadium sections for real-time chat, fan signs, and polls via Socket.IO. White-labeled for ESPN.