Marcin Korolko
From: Poland
Location: Warszawa, PL
On Useme since 24 December 2024
Deals 3
SUCCESSFUL: 3
DISPUTED: 0
FAILED: 0
About me
I build software for small businesses: web, desktop and mobile apps, automations, reports, and connections to the systems you already use (e.g. Subiekt GT).
Live client projects: - Footwear workshop: order flow between departments, replacing signed paper slips. Barcode scanning, one-click printing, read-only data from Subiekt GT. In use since September 2026. The client ordered another paid version (review on this profile). - Optical retail chain: promo-code system with nightly email reports, in production since May 2026. - Inventory and sales dashboards, plus automated report delivery.
Side project: a hiking and outdoor app for Android and iPhone (Flutter, Firebase), in testing. Offline maps, offline route planning, and group trips.
Screenshots and descriptions: tidenza.com/pl/realizacje/ (in Polish)
Scope and fixed price in writing before we start. For apps with a user interface, mockups come first. Tell me in a few sentences what you currently do manually, and I'll reply with scope and price.
Categories
Portfolio
Browser app for a shoe workshop: each department scans the order barcode when its step is done, the manager sees overdue orders on one screen. Reads Subiekt GT without changing it. In use since 09/2026, the client ordered two further versions.
Czarny Sport: menedżer żużlowy w przeglądarce
Speedway management game in plain HTML and JavaScript (about 31k lines, no engine): continuous-time race simulation with animation, club AI, economy, 3 leagues, 2-4 players on one device, 103 test files. In development, demo-build screenshots.
Menedżer skryptów prowadzący procesy ETL
Runs scenarios in sequence or in parallel on a schedule, copies files before and after processing, repairs common input errors on its own, takes commands by mail and returns a report from every run. In use at a client.
The studio's own project: layout, brand identity built on a wave motif, PL/EN copy and the site code. A showcase of the video, audio and web services, made in an AI-assisted, human-directed model.
A series of offer covers laid out in code (HTML to PNG): full control over typography, a consistent identity, and variants tested for click-through.
My own app (Flutter, Firebase): offline maps of 12 mountain regions, route planning on marked trails, route guidance with off-route alerts, group trips with shared positions and an alarm. In closed testing (Google Play, TestFlight).
System kodów promocyjnych dla sieci salonów
A Tkinter desktop app and a Flask web app on one SQLite database: accounts with permissions, nightly KPI mail, a watchdog that brings the service back up after a server restart. In production since May 2026 and still maintained by me.
Generator grafików pracy z solverem OR-Tools
Desktop and web on a shared database, multiple locations, accounts with permissions. An OR-Tools CP-SAT solver places the shifts, taking working-time limits as model constraints. Finished and past its pilot; not yet running at a client.
A complete brand for a music project (funky house): name, website, release covers and identity. Music produced in-house with AI tools under my direction. The project that started our studio's way of working.
A starter pack for a maker of grain-weighing probes: a 33-second teaser cut from the client's own material (colour grading, original music), a logo with an emblem, and an offer page in two variants. From brief to the full set in 3 days.
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