developer.ts
const developer = {
name: 'Stanislaw Zajaczkowski',
role: 'Front-end Developer',
stack: ['React', 'TypeScript', 'Next.js'],
at: 'Operend',
background: 'PhD, human physiology',
learning: 'AI-assisted dev',
available: false // happily building @ Operend
}

From the lab
to the browser.

Front-end developer with a scientist's mindset. I turn messy, data-heavy problems into clean, fast React interfaces — and I'm always learning what's next.

Stanislaw Zajaczkowski
@ Operend

I didn't take the usual route into code — and that's exactly my edge.

I earned a PhD in human physiology at the Medical University of Gdańsk — years of research, data and rigor. I'm a biologist by training (not a physician), and at some point I realized the thing I most wanted to build was software.

That science background still shapes how I work: I pick up complex domains quickly, I care about correctness, and I'm comfortable turning data-heavy problems into interfaces people actually enjoy using. Today I build with React and TypeScript at Operend — and previously built data-heavy web apps for commercial clients at inspeerity — from clinical research dashboards to industrial analytics.

I'm not standing still: I'm going deeper with the Developer Jutra program — architecture, product thinking and using AI as a genuine co-engineer across the full stack — the next layer beyond the front-end.

4+ yrs
building for the web
PhD
medical sciences
EN / PL
fluent

$ git log --author=staszek

The road from a physiology lab to a React codebase — most recent first.

2025 — now
NOW

Learning, always

Developer Jutra · AI-assisted dev

Going deeper with Tomasz Ducin's Developer Jutra program — architecture, product thinking and using AI as a genuine co-engineer across the full stack. The next layer beyond the UI.

Jul 2025 — Present
Boston, MA · Remote

React Developer

Operend ↗

Building data-heavy web applications in React and TypeScript, with a focus on clean architecture and maintainable code.

Mar 2024 — Jul 2025
Białystok · Remote

React Developer

inspeerity ↗

Owned scalable, performant front-end features across React, TypeScript, Next.js and Tailwind CSS, building data-heavy apps for commercial clients — from clinical research dashboards to industrial analytics.

Dec 2021 — Mar 2024
Białystok · Hybrid

Junior React Developer

inspeerity ↗

Developed and maintained React applications and built strong front-end foundations while collaborating with designers and back-end teams.

Feb 2021 — Nov 2022
Gdańsk · Remote

Junior Front-end Developer

Enterosoft ↗

Built and maintained multilingual Gatsby + React sites, improving performance and accessibility through careful JS, HTML and CSS work.

2020
Gdańsk

Front-end Bootcamp (240h)

infoShare Academy ↗

An intensive front-end programming course — the deliberate switch from science to software.

2010 — 2019
Gdańsk

PhD, Human Physiology

Medical University of Gdańsk (GUMed) ↗

Doctorate in medical sciences, with a background in biology (not a physician). Years of research, data and rigor that still shape how I build software.

Own Projects

all_on_github →
Game in JS

Game in JS

A browser game built in pure JavaScript on an object-oriented core, with a Firebase Firestore leaderboard for the winners. Small, fast, and fun to poke at.

HTML5HTML5
CSS3CSS3
JavaScriptJavaScript
FirebaseFirebase
GitGit
Notes & Todos

Notes & Todos

A React + Firebase app for managing notes and todos, with real-time persistence and a clean, focused UI. Built to actually be used day to day.

HTML5HTML5
CSS3CSS3
styled-componentsstyled-components
JavaScriptJavaScript
ReactReact
ReduxRedux
REST APIREST API
FirebaseFirebase
GitGit
Joanna Miklosz — science site

Joanna Miklosz — science site

A landing page for Joanna Miklosz PhD, with a Cloud Functions + Brevo contact pipeline. Bridging my science world and my dev world.

HTML5HTML5
CSS3CSS3
JavaScriptJavaScript
BootstrapBootstrap
FirebaseFirebase
GitGit
Shopping-List App

Shopping-List App

A Vanilla JS shopping-list app bundled with Webpack 5, styled with Bootstrap 5 and backed by Firebase. A study in doing more with no framework.

HTML5HTML5
CSS3CSS3
BootstrapBootstrap
JavaScriptJavaScript
REST APIREST API
WebpackWebpack
FirebaseFirebase
GitGit

Skills & tech

ReactReact
JavaScriptJavaScript
ReduxRedux
styled-componentsstyled-components
HTML5HTML5
CSS3CSS3
BootstrapBootstrap
FirebaseFirebase
REST APIREST API
GitGit
TypeScriptTypeScript
Next.jsNext.js
Tailwind CSSTailwind CSS
shadcn/uishadcn/ui
Material UIMaterial UI
MUI Data Grid ProMUI Data Grid Pro
TanStack QueryTanStack Query
TanStack TableTanStack Table
TanStack FormTanStack Form
TanStack RouterTanStack Router
React RouterReact Router
AgileAgile
// currently_learning
Developer Jutra — architecture, product thinking & AI as a co-engineer (Tomasz Ducin) · full-stack delivery · AI-assisted development.
// certifications
React Query — query.gg (2025) · Just JavaScript — Dan Abramov (2025) · Front-end Bootcamp — infoShare Academy.

Contact me

I'll get back to you within a day or two.