B2B2C micro-frontend platform
20+ Vue apps living in single-spa, talking to each other in real time. GraphQL, REST and SignalR under one roof.
Szczepan Kosik — Senior Frontend Engineer Available · part-time · B2B
Frontends that scalewith your business.Not against it.
10+ years turning complex products into fast, typed, maintainable interfaces. Vue 3 · Nuxt · TypeScript. Tech lead by habit, not by title.
- Base
- Lublin, PL
- Coords
- 51.25°N 22.57°E
- Local time
01 Approach
Performance is your money.
01
Every wasted request is a line on someone's invoice. I hunt them down.
I never listen passively.
02
Refinements are for challenging ideas. Including mine.
Quality is automated, not negotiated.
03
Strict types, lint rules and git hooks. Standards that hold when nobody is watching.
I build interfaces I'd want to use myself.
04
I click through them like an end user. If something bothers me, I fix it before anyone else notices.
02 Impact
Numbers, not adjectives.
- 01
10+
Years shipping production frontends
- 02
20+
Micro-frontends in one living platform
- 03
5+
Years with the same client — and counting
- 04
11+
Projects shipped to production
03 Selected files
Classified work.
Most of my projects live behind NDAs. So here are the case files — names redacted, results intact.
Performance rescue: Vue 2 → 3
A rewrite that was slow before it shipped. Hard lint rules, a centralised query layer and real-time invalidation made it as fast as it gets.
Cloud translation cost cut
Every translation publish fanned out across all clusters, languages and apps. I traced it and cut it to one app, one request. Plus a script that merged per-feature i18n files and rewrote every key in code.
Weekly meal planner
I proposed drag & drop everywhere. Planning a week of meals went from clicking through forms to rearranging the screen in seconds.
Vue component library in Storybook
Designed and shipped a Vue component library in Storybook, standardising UI patterns and speeding up feature development.
Per-feature Kubernetes environments
Used Docker and Kubernetes to stand up isolated environments per feature, and worked on the micro-frontend ecosystem's Azure CI/CD pipelines.
wirtualnycmentarz.pl
Vue 2 + TypeScript with SSR and complex screen transitions. Service Worker caching for assets and data, IntersectionObserver-driven lazy loading, and canvas-based weather visualisations. My first big one — fitting, given my taste in films.
04 Stack
Tools I trust.
Core10+ yrs
- Vue 301
- Nuxt02
- TypeScript03
- Tailwind CSS04
What I think in. Daily, for years.
queries/orders.ts
1// one typed source of truth2export const orderKeys = {3 all: ['orders'] as const,4 detail: (id: string) => [...orderKeys.all, id] as const,5}6 7// real-time: invalidate exactly what changed8hub.on('OrderUpdated', ({ id }: OrderEvent) =>9 queryClient.invalidateQueries({10 queryKey: orderKeys.detail(id),11 }),12)NORMALThe fix that made a slow rewrite fast: typed query keys + targeted real-time invalidation.ts · utf-8
Data & real-time
- GraphQL · Apollo
- TanStack Query
- SignalR
- REST
- single-spa
- Pinia
Backend
- NestJS
- Express
- Node.js
- PHP · Laravel
- .NET
- PostgreSQL
- Redis
- MongoDB
Quality gates
- Vitest
- Cypress
- Storybook
- Biome
- Git hooks
- Strict TS
- Code review
Infra & delivery
- Docker
- Kubernetes
- Azure
- CI/CD
- Linux · VPS
AI / LLM
AI-assisted workflow and LLM integrations — a multiplier, not a replacement for thinking.
Neovim keys. Inside VS Code.
Yes, I know how to exit. I just rarely want to.
:wq
05 Process
How I work.
“He compiles code just by looking at it.”
01
Question
I challenge the ticket before I write the code. The cheapest bug is the one never built.
02
Architect
Clear boundaries, typed contracts, no hidden coupling. Components built to be reused.
03
Guard
Strict linting, formatting, pre-commit and pre-push hooks. Reviews that notice what isn't obvious.
04
Deliver
Fast for users, cheap to run for the client, readable for the next developer. Along the way: mentoring and technical interviews with candidates.
06 Contact
Got a productworth doing right?
Available part-time, B2B, remote. Tell me what you're building — I reply within one business day.
Prefer email?