Michał
Zagalski
10+ years delivering high-performance web applications that drive measurable business results — including performance engineering that lifted user engagement 23%, grew organic traffic 35%, and reached a perfect PageSpeed 100 on a real-time SSR app on Cloudflare Workers. Deep expertise in scalable edge architecture, AI integration, Web3, and open-source library authorship; adept at translating complex technical requirements into business outcomes across TypeScript, Go, Python, and PHP, and leading small delivery teams.
Performance
100/100
PageSpeed Score
Experience
10+ Yrs
Full-Stack Dev
Location
Warsaw
Poland / Remote
Work Experience
01 // PROFESSIONAL JOURNEY
Lead Consultant / Contractor
Senior Full-Stack Engineer
May 2019 - Present
Warsaw, Poland
- DexPaprika (CoinPaprika) — real-time DEX explorer: Collaborated with a product team of 5 to migrate from Vue 3 to Nuxt 4 SSR on Cloudflare Workers; led an 8-phase performance program that lifted user engagement 23% through sub-second loads (PageSpeed Desktop 100, Mobile 95.6, CLS 0.000). Re-platformed Bootstrap to Tailwind CSS v4 (53% CSS reduction) and shipped a 3-tier stale-while-revalidate edge cache with critical-CSS injection. Owned the visual redesign and mobile UX rewrite (thumb-bar navigation, swipe gestures, design-token component drawer, TV board mode); raised markdown, llms.txt, and structured-data agent-readiness to 100.
- CoinPaprika — cryptocurrency data platform: Working with a cross-functional team of 8, architecting a Next.js 15+ migration of a legacy PHP/Vue 2 platform on a Turborepo (pnpm workspaces); coordinating the roadmap with product and business stakeholders for a zero-downtime transition. Shipped the official CoinPaprika PHP SDK v1.5.0 and Node.js API client v3.0.0 (21 new endpoints, native fetch, retry/AbortSignal, dual CJS/ESM, CI), plus an AI Article-Writer Assistant (Cloudflare D1, Durable Objects, multi-LLM: Claude / OpenAI / OpenRouter).
- GetName.pl — premium .pl domain marketplace: Sole technical lead reporting directly to the founder; delivered the MVP in 8 weeks. Built a Nuxt 4 marketplace (11 feature layers) with full NASK EPP registry integration and a Web3 layer (Solidity: GNRegistry, GNMarketplace, GNToken ERC-20, NFT domains on Polygon). Implemented real-time anti-snipe auctions, an AI domain-valuation assistant (OpenAI), multi-payment (Stripe, Przelewy24, crypto), and SIWE auth (MetaMask / WalletConnect / Coinbase / Safe). PostgreSQL (40+ tables), Redis, Drizzle ORM, Better Auth.
- DOMAR — e-commerce & business platforms: Coordinated directly with the business owner to migrate a legacy PHP e-commerce platform (8,000+ products) to Next.js 16 / React 19 with PostgreSQL, Drizzle, Valkey, and Polish full-text search; improved organic traffic 35% through an SEO-optimized architecture (ISR, RFQ). Built multilingual Next.js 15/16 + PayloadCMS sites on Cloudflare D1/R2 with a Claude-API content pipeline and 120+ automated SEO scripts, plus zlecenia.domar.biz.pl — a Laravel order-management app for a door & window company's individual customer orders.
- LeoKlima.pl — HVAC company site: Migrated to Next.js 15 + PayloadCMS with an automated lead-generation pipeline that increased qualified leads 40%; deployed on Cloudflare edge for sub-100ms response times nationwide (multilingual PL/EN/UA, Turnstile, JSON-LD).
- Veterinary Management System: Delivered end-to-end — from requirements-gathering with clinic staff to production deployment — a Next.js 15 clinic-management app with Stripe payments, medical records, a business-analytics dashboard, and Fabric.js annotation, replacing a 20-year legacy system with zero downtime.
- Selected additional delivery: Led a team building a Vue 3 / Vuetify digital-signage platform (McDonald's locations); migrated a roofing company from Astro to Next.js 15 + PayloadCMS; delivered enterprise contract engagements (SoftWizards "Profix" suite; an Azure DevOps digital-signage platform); and built a Vue + Django + MLflow workflow UI and a Rust + SwiftUI iOS fitness app.
Levitated.pl
Software Developer
2017 - 2019
Remote
- Developed PHP REST API for property geolocation.
- Managed CraftCMS websites and built a Django platform for personal trainers with Stripe payments.
Polcode
Software Developer
2016 - 2017
Warsaw, Poland
- Built a Yii2 coupon generation app and an Angular + Laravel volleyball coaching toolkit.
- Handled e-commerce bug fixes for legacy Laravel/jQuery applications.
Akademia Nauki
Software Developer
2015 - 2016
Warsaw, Poland
- Developed a Laravel mailing system for newsletter campaigns.
- Managed Moodle e-learning platforms.
Technical Arsenal
02 // SKILLS & TOOLS
Languages
Frontend
Backend
Edge & Cloud
Databases
AI & LLM
Web3
Tooling & Test
Publications
03 // TECHNICAL WRITING
Open Source
04 // COMMUNITY CONTRIBUTIONS
arachnit-crawler
Self-hosted SEO crawler & auditor: 50+ on-page/technical checks, semantic duplicate detection, cross-crawl regression tracking. Next.js 16, React 19, Node 22, BullMQ, PostgreSQL 18 + pgvector, Valkey, Transformers.js local embeddings. AGPL-3.0.
przelewy24-ts-sdk
First-party TypeScript SDK for the Przelewy24 payment gateway: transaction registration, SHA-384 webhook verification, refunds, multi-currency, zero runtime deps, ESM+CJS, with Nuxt 4 and Next.js 15 adapters.
design.md (Google Labs)
Authored an open-source PR adding a `design.md import` reverse command that generates a DESIGN.md from a Node.js project via static analysis (framework detection, Tailwind v3/v4 config and CSS custom-property parsing, icon-library inference); ~4,300 LOC across 51 files.
browser-curl
WAF resilience testing tool: validates web-application-firewall configurations by simulating real Chrome request patterns (headers and HTTP/2 fingerprinting). MIT.
parallel-requests
Claude Code skill that detects sequential independent HTTP calls and refactors them into parallel execution.
nask-epp-client
TypeScript client for the NASK EPP protocol (Polish .pl domain registry).
figma-exporter
Node/TypeScript CLI that bulk-exports an entire Figma account (incl. .fig binaries) via Playwright browser automation; resumable, with zip bundling.
iledcolor
Pure-Python, local-first Bluetooth-LE driver and CLI for RGB LED panels; reverse-engineered the vendor protocol to replace a privacy-invasive vendor app.
Conferences
05 // CONTINUOUS LEARNING
Education
06 // ACADEMIC BACKGROUND
B.Sc. Electrical Engineering
Warsaw University of Technology
2014 - 2018
Additional Learning
07 // BOOKS & COURSES
Interests
08 // BEYOND THE CODE
Let's build something fast.
Currently open to senior roles, performance consulting, and high-stakes engineering projects.
Get in touch© 2026 MICHAŁ ZAGALSKI
BUILT WITH REACT + EXPRESS + TAILWIND V4
WARSAW, PL // 52.2297° N, 21.0122° E