Hi! I'm Zack.
I'm a full stack developer and life-long learner with a deep passion for problem solving and tech. With a rich background in the music industry, working alongside artists and music labels, I've transitioned my creative mind and audio engineering skills into the world of software development. When I'm not at my computer, I like to spend my time learning Japanese, keeping fit and producing music.
Experience
Zack Hanni
Software Engineer
I build exceptional and accessible digital experiences for web and mobile.
Senior Software Engineer
Leadr
August 2025 - Present
Senior member of a cross-functional feature team building enterprise SaaS products using React, TypeScript, and Nest.js—delivering full-stack features, scalable UI architecture, AI-assisted insights, and real-time analytics dashboards supporting executive decision making across large organizations.
- Architected modular enterprise dashboards using React 18, TypeScript, and TanStack Query, enabling real-time visibility into engagement, performance, and organizational health across 10+ data domains.
- Designed centralized query key and caching architecture improving API data consistency and reducing redundant network calls across parallel queries.
- Built scalable component systems and shared design system foundations used across 20+ product feature modules.
- Designed centralized state architectures using Context + useReducer patterns to manage multi-dimensional filtering, workflow state, and assessment lifecycle orchestration.
- Built 25+ reusable custom React hooks for data fetching, mutation handling, and cache invalidation, establishing reusable data patterns across the codebase.
React Developer (w/ Node.js)
Fedstack / Leidos
May 2025 - July 2025
Developed a mission-critical Single Page Application (SPA) for the Federal Aviation Administration (FAA) to enable real-time flight path monitoring, editing, and airspace management.
- Built advanced geospatial features using React Leaflet, GeoJSON, and Polylines to visualize dynamic aircraft positions and projected trajectories.
- Engineered a Reroute Tool supporting interactive route drawing, conflict detection, and path validation for safe airspace operations.
- Led state management migration from React Context to Zustand, improving performance and stability across the application.
- Simulated real-time aircraft movement using interval-based coordinate updates for real-time animation and optimized rendering.
- Resolved complex rendering bugs including event propagation issues, race conditions, and improper state updates.
- Collaborated with UX/UI designers in Figma to translate interactive prototypes into pixel-perfect React components, ensuring visual accuracy and accessibility compliance.
Full-Stack Developer
SmartMark Communications
August 2023 - April 2025
Led full-stack development of web, mobile, and IoT platforms using React Native (with Expo), Next.js, Node.js, and AWS, delivering performant cross-platform applications.
- Developed a React Native IoT Smart Home App integrating SmartThings and Home Assistant APIs, enabling control of 100+ smart devices.
- Built a real-time Node.js server using Express and Apache Kafka, exposing RESTful API endpoints for downstream consumers.
- Created a lightweight CRM platform with Next.js and SQLite, supporting lead management, annotations, and OAuth 2.0 via Microsoft Identity Platform.
- Built a location-based mobile quiz game with 500+ users, using analytics for engagement tracking and automated prize distribution.
- Maintained and deployed 16+ production websites via AWS and GoDaddy, automating updates and improving efficiency across 10 servers.
Front-End React Developer
Sounds Like Soma
January 2019 - August 2023
Developed and maintained web applications for recording studios and independent artists, focusing on reusable tooling, SEO growth, and scalable multimedia data systems.
- Developed reusable press kit templates in React adopted by 20+ artists and labels, deployed globally through Vercel.
- Rebuilt the studio's main site using Rails, Jekyll, and Bootstrap, achieving 5+ years of continuous SEO-driven traffic growth.
- Managed 50+ TB of multimedia data across 4 studios, building secure archive and retrieval systems.
Side Projects
About
🌱 How It Started
My journey into software began with late nights on Codecademy, a patient mentor, and hands-on learning through freelance gigs. Things took off at Sounds Like Soma, a Philadelphia-based recording studio, where I built and maintained the studio's web presence and IT infrastructure over five years. There, I collaborated with global recording artists and record labels—designing promotional landing pages and crafting reusable electronic press kit templates that were adopted by 20+ artists and deployed through Vercel.
👨💻 Where I Am Now
I'm currently a Senior Software Engineer at Leadr, where I build enterprise SaaS products used by managers and organizations to improve performance, communication, and team health. My work spans architecting modular analytics dashboards, designing scalable component systems, and building the custom hooks and caching patterns that power data-heavy features across the platform. Prior to Leadr, I led full-stack development at SmartMark Communications—shipping cross-platform apps in React Native and Next.js—and built a mission-critical flight path monitoring SPA for the FAA as a contractor with Fedstack and Leidos.
🔍 What I'm About
I specialize in the React and TypeScript ecosystem—building high-performance frontends, reusable design systems, and real-time analytics interfaces that support data-driven decision making at scale. I thrive in collaborative environments that value clean architecture, shared knowledge, and software that genuinely improves people's work. If you're building something meaningful and need someone who can own complex UI problems end to end, I'd love to connect.
Tech Stack
Mobile Development
Drop a line
This website was designed in Figma, coded in Visual Studio Code, built with Next.js, and deployed with Vercel by yours truly.