Kasia Walter — Frontend Engineer

React · TypeScript · Next.js · Tailwind · design systems in code · AI-directed development. 4.5 years in production web, all of it at Pirxey (Widelab). Based in Poland, works EU remote.

What I do

I build React and TypeScript product applications, and design systems in code: design tokens, component APIs, and the rules that keep a system from drifting once several people are shipping into it.

I own the architecture of the design systems I build. Other developers ship into my component APIs, and I review what lands.

I direct AI coding agents against a method and a review I wrote myself, and I read every diff before it ships. AI moved the bottleneck from typing to judgement. Judgement is the part I am good at, and the responsibility stays with me.

Something is wrong and nobody can name it yet — that is the moment I am for. I go under the surface and fix the structure, not the symptom.

Positioning

I work as a frontend engineer: product React, TypeScript and design systems are the day job. Not a designer who also codes, and not an animation contractor. Motion and WebGL are where I prove engineering depth — a render loop, a frame budget, a GPU tier — not the category I work in.

Evidence

Awwwards Developer Award and Site of the Day, February 2024, for the cuewigs frontend build. Awwwards gives that award to the developer, not to the studio.

Pirxey (Widelab), February 2022 – present. Web developer first — motion-led sites in GSAP. React developer since July 2024 — product applications and design systems in code.

This site — a real-time WebGL engine written from scratch, sharing a render loop with a React app.

Stack

• Core — React, TypeScript, Next.js, Tailwind CSS, SCSS, JavaScript (ES6+), HTML5, CSS3, Vite.
• Design systems — design tokens, component API design, scalable component architecture from scratch, Storybook, fluid responsive systems, Figma.
• AI in the development cycle — Claude Code, AI agent workflows, custom agent skills, persistent-memory agents, structured output, review of AI-generated code.
• State and data — Redux Toolkit, RTK Query, TanStack Query, Zustand, React Hook Form, Zod, REST APIs.
• Testing and code quality — Jest, Vitest, React Testing Library, Playwright, Cypress, peer code review.
• Performance — frame budgets, GPU tiers, render optimisation, mobile performance, layout read once a frame.
• Accessibility — semantic HTML, focus management, reduced-motion paths, screen-reader support.
• Motion and graphics — GSAP, Three.js, WebGL, Lenis, scroll choreography.

Selected work

cuewigs — I wrote the frontend. The GSAP implementation, the responsive system and the performance are mine; the design and the motion spec came from the designer. The layout scales as one continuous system: everything in rem, the root font-size interpolated against the viewport, so nothing jumps between breakpoints. That one was my call. Awwwards Developer Award and Site of the Day, February 2024 — Awwwards gives that one to the developer.

kasiawalter.it — this site. A real-time engine sharing a render loop with a React app: Three.js and TypeScript, written from scratch — custom geometry, additive sprite and line rendering, bloom post-processing. It holds on a mid-range phone because I made it hold — the GPU is tiered and effects are dropped by cost, scroll work is rAF-coalesced, and layout is read once a frame. Reduced motion switches the engine off and the page still reads. Built by directing AI agents with persistent memory, every diff reviewed by me.

Design-direction methodology — an agent skill of my own, written in my own time and used in production work: research in four lenses, a semantic brief with an approval gate, reverse-reading as the selection step, and blind subagents generating competing directions. Nobody assigned it. I wrote it because directing agents without a method produces confident, generic work.

Contact

Open to frontend engineering roles where motion is treated as engineering, not decoration, and where AI is directed and reviewed rather than pasted in. EU remote, based in Poland.

Email: kasia.walter.it@gmail.com

LinkedIn: linkedin.com/in/kasia-walter