Hi, I'm

Josef Jadrny

Senior Software Engineerfull-stack TypeScript · AI-first

I build web products end to end with AI agents in the loop - Node.js and TypeScript on the backend, React on the frontend, and the AWS infrastructure underneath. 14 years in, based in Prague.

Josef Jadrny
“I simple code”

01 · About

A simple code

I'm a full-stack engineer who cares about code that is easy to read, easy to change and boring to run in production. I've led teams through big migrations (PHP to Node.js & React, on-premise to AWS), shipped SDKs used by over a million TV viewers, and today I work on one of the best-rated CRMs at Pipedrive.

AI is how I work now, at Pipedrive and on my own projects below. opinio.live is built and run by me and AI agents - they do the work, I stay in control - from the database to the Android app, including AI-written news, translations and content scoring in production.

  • 14years of experience
  • AI-firstsince 2025
  • 21k+monthly npm downloads

Languages

  • TypeScript
  • JavaScript
  • SQL
  • PHP

Backend

  • Node.js
  • Fastify
  • GraphQL / Apollo
  • PostgreSQL
  • Microservices

Frontend

  • React
  • React Native
  • Vite
  • Tailwind
  • PWA

Cloud & DevOps

  • AWS
  • Kubernetes
  • Docker
  • GitHub Actions
  • Cloudflare
  • On-call

AI

  • Claude Code
  • AI agents
  • Agentic workflows
  • MCP
  • LLM APIs
  • AWS Bedrock
  • Prompt engineering

02 · Experience

Where I've worked

  1. Pipedrive Current

    Senior Software Engineer

    - Present

    Pipedrive is one of the best user-rated CRM tools, with a focus on small and mid-size companies. As they use the tribes & missions framework, I joined Prague's tribe (instead of a team).

    As a full-stack JavaScript software developer, I work with Node.js and TypeScript on the backend and with React on the frontend. I am also part of the on-call team, which takes care of microservices running in production.

    Since 2025 I've worked AI-first and I'm one of the heaviest AI users in my tribe. AI agents write, test and review most of my code - I steer them and stay in control of what ships.

    • TypeScript
    • Node.js
    • React
    • Kubernetes
    • Microservices
    • Claude Code
    • AI agents
  2. Nangu.TV

    GraphQL Software Developer

    -

    Nangu.tv's IPTV/OTT solution has more than 1 million users in Central Europe - it is used by major operators like O2 and Orange.

    As part of the GraphQL team, I worked with Node.js and Apollo, and I was responsible for developing and maintaining a unified JavaScript SDK written in React/React Native for our clients' frontends.

    • GraphQL
    • Apollo
    • Node.js
    • React Native
    • SDK
  3. Economia

    Head of Development · Software Developer Lead

    -

    My first job in Prague was at Economia, one of the biggest Czech media houses, with brands like aktualne.cz, DVTV, Hospodářské noviny, and RESPEKT.

    We decided to replace PHP with Node.js & React, move from on-premise to the cloud (AWS), and adopt DevOps. As a team leader, I drove those changes while coding and mentoring others. It took almost a year to accomplish at centrum.cz, and I gave a talk about it at ReactiveConf 2019.

    Finally, after a few years, I moved into the Head of Development role to help roll out these changes company-wide.

    • Leadership
    • Node.js
    • React
    • AWS
    • DevOps
    • Mentoring
  4. AtNat

    Software Developer

    -

    AtNat was an ambitious startup. Back then, it was challenging to create an isomorphic JavaScript web application. It was my first encounter with Node.js and Angular.

    • Node.js
    • Angular
    • Isomorphic JS
  5. Digital Solutions

    Software Developer

    -

    Digital Solutions is a smaller IT company specializing in information systems (B2C), with clients like MMReality (the biggest real estate agency in the Czech Republic).

    I spent most of my time working on MMReality's internal system, written in PHP and JavaScript, with a strong focus on code quality. It was my first real experience with advanced programming techniques like OOP, Clean Code, Agile, etc., and with document-based databases.

    • PHP
    • JavaScript
    • OOP
    • Agile
  6. eBRANA

    Junior Software Developer

    -

    My very first professional experience began at eBrana immediately after graduating from the University of Pardubice. I started with PHP and vanilla JavaScript, creating and updating features on clients' e-shops to fit their needs.

    • PHP
    • JavaScript
    • E-commerce

03 · Projects

Things I've built

opinio.live

Solo product

A global social voting platform - browse and vote on statements, events and public figures by country on an interactive world map. Built and run alone, from the database to the Android app.

  • React
  • Fastify
  • PostgreSQL
  • AWS ECS
  • Cloudflare Workers
  • Android TWA

js-chess-engine

Open source

A complete chess engine in TypeScript with zero dependencies, for Node.js and browsers. Configurable AI with five difficulty levels, stateful and stateless APIs, JSON and FEN support.

  • TypeScript
  • Algorithms
  • npm
  • 168 ★

js-idb

Open source

A lightweight JSON database for TypeScript with schema validation, indexed search and sorting. Zero dependencies, in-memory or file-persisted, for Node.js and the browser.

  • TypeScript
  • Databases
  • npm

04 · Contact

Let's build something simple.

If you'd like to work with me, want more information, or just feel like a chat, send me an email.