Open to new opportunities

Piotr Zięcina

Full Stack Developer

I build web applications end to end, from discovery workshops with clients to releases in production. React, Next.js and Vue on the frontend; Node.js, NestJS and SQL on the backend. 4+ years of commercial experience, most recently at SmartBear.

View projects →piotr@ziecina.dev

Wrocław, Poland · open to remote and hybrid

Portrait of Piotr Zięcina — React · Next.jsNode.js · NestJSMySQL · PostgreSQL

Projects

Built, shipped, used.

Two products I designed, built and deployed on my own. One runs a real business every day; the other is open source.

In productionReal client2026 – present

Stajnia Lauden

A production web app that runs the daily work of a horse boarding stable with 60+ boxes.

The stable used to coordinate services, feeding and turnout over social media messengers. I replaced that with one web app used every day by the owners (admins), staff, trainers, horse owners and lessees on phones, tablets and wall-mounted screens.

5 user roles130+ unit tests100+ e2e testsPWA + Web Push

Next.js · TypeScript · Tailwind CSS · NestJS · Prisma · PostgreSQL · PWA & Web Push · Docker · Caddy · GitHub Actions · Jest · Supertest

Read the case study →stajnialauden.pl ↗

Commercial product. Source code is private; I'm happy to walk through it during an interview.

demo data · details blurred

Stajnia Lauden staff task board: a grid of numbered boxes with open tasks highlighted

Open sourceLive demo

Build Budget

Track a house build: stages, expenses against budget, documents and bank-ready PDF reports.

I'm building my own house and wanted one place for everything about it. Build Budget splits the build into stages and keeps each stage's budget, receipts, documents and photos together, shared in real time with everyone on the project.

JWT access and refresh tokens in httpOnly cookies, with silent refresh. I found and fixed a race condition where parallel requests were refreshing the token at the same time.
Stripe subscriptions with signature-verified webhooks. The free plan is limited to one project.
PDF bank reports generated in the background with Redis and BullMQ.
Real-time collaboration: project members see each other's changes live over WebSockets.

More highlights (3) ↓

Document uploads straight to S3 with presigned URLs, plus a construction diary with photos.
Bilingual UI (PL/EN) with next-intl.
CI runs unit tests (80% coverage thresholds on files with logic), end-to-end tests against a real database, and builds both apps.

Next.js · TypeScript · Tailwind CSS · TanStack Query · NestJS · Prisma · PostgreSQL · Redis · BullMQ · Socket.io · Stripe · AWS S3 · Docker · GitHub Actions

Read the case study →Live demo ↗Code on GitHub ↗

Experience

Where I've worked

2024 – present
Software Developer · SmartBear
Two AI-powered testing products: Reflect (Vue.js, Scala) and Visual Test (React, Next.js, NestJS). Built features on the company's in-house LLM: requests to its API and handling the responses in the product.
- Designed and built a test-data lookup, frontend and backend, that became the customer support team's main tool.
- Cut security vulnerabilities by 40% through systematic dependency audits and upgrades.
2022 – 2024
Full Stack Developer · Ampcasd
Led a team of 4 building a CMS and a booking and payments platform for a cultural centre in Germany, from discovery to launch in about a year.
- Grew the platform to 1,600+ users and 1,800+ subscriptions sold.
2019 – 2022
Electrical Supervisor · KNAPP
Supervised construction of automated warehouse and shipping systems for clients such as Tiffany, Kroger, Adidas and M&S.

Full CV (PDF) →

Skills

What I work with

Frontend

React, Next.js, Vue.js, TypeScript, Tailwind CSS, PWA, SSR/ISR

Backend

Node.js, NestJS, Prisma, TypeORM, PostgreSQL, MySQL, REST, GraphQL, WebSockets, Redis, BullMQ, Scala (commercial)

AI

In-house LLM integration via API (SmartBear), AI agents in Claude: plan mode, agentic workflows, spec-driven development, custom skills and requirements in Markdown

Cloud & DevOps

AWS, Docker, Terraform, GitHub Actions, Caddy, VPS

Quality

Jest, Vitest, React Testing Library, Playwright, Supertest, unit and end-to-end testing, dependency auditing

Integrations & tools

Stripe, PayPal, SEPA Direct Debit, Amplitude, Web Push, Figma, Jira, Git

About

From warehouses to web apps

Before software I was an electrical supervisor at KNAPP, building automated warehouses for global brands. That's where I learned to work to deadlines and specs and to coordinate with people on site.

Today I build web applications, and the part I enjoy most is the whole loop: understanding what a client really needs, building it and seeing it used every day. I care about tests, clear decisions and software that's simple for the people using it.

Based in: Wrocław, Poland
Education: BSc, Electronics and Telecommunications, Wrocław University of Science and Technology
Languages: Polish (native) · English (B2), used daily in an international team
Looking for: Full stack or frontend role, remote or hybrid

Contact

Let's talk.

I'm looking for a full stack or frontend role. If you think I'd be a good fit for your team, write to me.

piotr@ziecina.dev

LinkedIn ↗GitHub ↗