Full Stack & AI Software Engineer
Nir Feinstein
Senior Full-Stack Engineer with 14 years of experience as a developer, educator, and app creator. I focus on writing clean, scalable, and maintainable production-ready code, turning complex problems into elegant digital solutions.
Skills
- React
- Next.js
- TypeScript
- NestJS
- Node.js
- Python
- FastAPI
- PostgreSQL
- MongoDB
- Redux
- Tailwind CSS
- Storybook
- Jest
- Playwright
- WebSockets
- OAuth2
- Microservices
- Docker
- Kubernetes
- Terraform
- AWS
- GCP
- Azure
- Serverless
- CI/CD
- LLM APIs
- AI Agents
- LangGraph
- MCP
- Electron
- Flutter
- Swift
- Android
My Portfolio
A collection of my professional jobs, freelance projects, personal products, and teaching.
Full Stack Works
5
Base.ai
Senior Full Stack Engineer: autonomous AI agent workflows with QA, code review and fix loops
- React
- NestJS
- Python
- AWS
Easysend
Senior Full Stack Engineer, frontend oriented: no-code journey builder for insurers and banks
- React
- TypeScript
- Python
- AWS
In-House Health
Full Stack Engineer: AI-driven nurse scheduling platform, built from the ground up
- React
- FastAPI
- GCP
Prometheus Inspiring Technology
Software Engineer: Android app and C# backend services
- Android
- C#
- Backend
IDF, Matspen unit (Mamram)
Software Engineer: C# enterprise systems, WCF services and WPF clients
- C#
- WPF
- WCF
Contract Developer
5
Insait
Senior Full Stack Engineer, contract: LLM assistants for banks and financial institutions
- React
- Node
- Python
- LangChain
- Docker
- Azure
Hexagate
Frontend Engineer, contract: Web3 security platform, now part of Chainalysis
- React
Suridata
Full Stack Engineer, contract: SaaS security platform, now part of Fortinet
- React
- Node
Dipio Systems
Android Developer, contract: push-to-talk instant communication app
- Android
Full Stack Bootcamp Lecturer
4
HackerU
Full Stack Lecturer: HTML, CSS, JavaScript, React and Node.js bootcamp
- HTML
- CSS
- JS
- React
- Node
Scale Up Velocity (Startup Nation Central)
Full Stack Lecturer: full-stack course in its tech talent programs
- HTML
- CSS
- JS
- React
- Node
Apps I Founded
12
OnlinePages
Landing Page and Personal Website Builder
- Founder & Developer
- SaaS
- Builder
- No-Code
Betterloop
Frontend Session Insights with Ranked Fixes
- Founder & Developer
- AI
- Analytics
- SaaS
Plainer
AI Collaborative Workspace with Files, Chat and an Agent
- Founder & Developer
- AI
- Productivity
- SaaS
WebSkins
Chrome Extension that Reskins Any Website with AI
- Founder & Developer
- AI
- Chrome Extension
Open Source
Tools I build and maintain in the open, mostly for AI agents and developer workflows.
- Agent prompt
most-capable-agent-system-prompt
System prompt and architecture for self-improving agents (870+ stars).
875 - Eval harness
RegressGuard
Self-hosted CI eval harness for prompt regression testing (Docker + CLI).
Python - MCP server
Conductor
Verified, retried and fallback-backed commands for Claude Code, served as MCP tools.
TypeScript - Claude Code plugin
Flipback
Claude Code plugin that resumes agents when announced work is left unfinished.
JavaScript1 - Agent auth
account-access
Scoped, resumable account access for coding agents, with OAuth renewal.
Python - Agent memory
Recall
Markdown and wiki-link memory layer for LLM agents, no vectors.
JavaScript - Android app
Handy AI
Android assistant that completes tasks on your phone (Kotlin).
Kotlin - CLI
standup
Generates a standup update from git commits in one command.
JavaScript - macOS utility
mac-keepawake
Keeps your Mac fully awake, even with the lid closed, and dims the backlight while it's shut.
Shell2
Let's Connect.
Got a project, a question, or just want to chat? I'm all ears. Drop me a line below or send an email my way.