Michał Składanowski — Senior Full-Stack Engineer

01 — Trajectory

Trained as an engineer. Now I build software.

My degree was in engineering — the discipline of understanding a system, finding where it breaks, and designing for load. That instinct stuck. Seven years later I apply it to code: same rigor, different material.

2022 — Present

Toggl↗

Remote

Senior Full-Stack Engineer React + Go · since 02.2025
Full-Stack Engineer 09.2024 — 02.2025
Frontend Engineer React, Next.js, TS · 01.2022 — 09.2024

Led a major frontend architecture refactor, migrating state management from Redux to React Query — collapsing data-fetching complexity and lifting developer velocity.
Drove the build-system move from Webpack to Vite, cutting build and hot-reload times for faster local feedback loops.
Designed and shipped reusable, accessible components for the company design system, standardising the product across multiple teams.
Refactored legacy backend code for readability, testability, and long-term maintainability.

2019 — 2021

mElements

Poznań, PL

Junior Software Engineer Java + React · 06.2020 — 12.2021
Technical Support Specialist 11.2019 — 06.2020

Built frontend and backend for Paynow, a high-volume payment processor operated for the largest bank in Poland.
Delivered white-label BLIK payment support for a Magento payment plugin, open source.
Supported merchants and partners integrating e-commerce platforms and the PSD2 mBank API — troubleshooting auth, consent flows, and API usage.

2018 — 2019

AdAwards Media Agency

Remote

Web Developer

Built and customised client sites on WordPress & WooCommerce, shipping production e-commerce and marketing sites with custom themes and plugins.

02 — Education

Where the engineering habit was built.

2019 — 2020

Collegium Da Vinci University

Poznań, PL

Postgraduate Studies Frontend Development

2014 — 2018

Poznań University of Technology

Poznań, PL

BSc in Mechanical Engineering Computerisation & robotisation of manufacturing

03 — Selected Work

Things I’ve moved the needle on.

A few pieces where the decision mattered — architecture, tooling, payments, and a project that’s entirely mine.

Side Project · Full-Stack + AI · Live

Comito.ai — AI Travel Planning Assistant

A full-stack, AI-driven travel planner that generates personalised day-by-day itineraries, optimised routing, and local recommendations from a traveller’s preferences. Designed, built, and shipped end to end.

LLMRouting / optimisationFull-stackProduct

Visit comito.ai ↗

Comito.ai landing page — the AI travel planner with a “Tell us where. We’ll handle the rest.” headline and a destination search.

Architecture

Redux → React Query migration

Rethought state management across the app, moving server state to React Query and shrinking the surface area teams had to reason about.

React QueryStateDX

Tooling

Webpack → Vite build system

Led the migration of the build pipeline, cutting build and hot-reload times and tightening the local feedback loop for everyone.

ViteBuildPerf

Design System

Accessible component library

Built reusable, WCAG-minded components adopted across teams — consistency up, feature delivery faster.

a11yComponentsDesign system

Payments

Paynow & BLIK at bank scale

Contributed across the stack of a high-volume payment processor for Poland’s largest bank, including white-label BLIK support.

JavaPSD2BLIK

My commits, open source ↗

04 — Stack

The tools on the bench.

Frontend

ReactNext.jsTypeScriptJavaScriptTanStack QueryReduxZustandTailwindHTML / CSSViteWebpackTurborepoAccessibility (WCAG)JestVitestRTLPlaywrightCypress

Backend

GoNode.jsGraphQLJava · Spring BootPHPPostgreSQLMicroservices

Infrastructure

Google Cloud (GCP)TerraformPub/SubDockerCI/CDGitHub ActionsGit

AI Tooling

Claude CodeCursorGitHub Copilot

05 — Contact

Got something worth building? Let’s talk.

Download CV ↓ Email ↗ LinkedIn ↗ GitHub ↗