AI product
Mejkit
Type what you want to build; AI returns a parts list and a step-by-step manual, exported to PDF.
Live product with its own shader-rendered 3D worlds
Open →Hire me
Full-stack developer who also solders.
I'm Jakub Matisko, based in Bratislava. I ship complete products on my own: web apps with payments and AI, desktop tools, firmware for microcontrollers and the circuit boards they sit on. Since May 2026 I've built around forty projects, the best of them below.
Open to freelance contracts, remote roles and on-site work in Bratislava.
Pads
Regions
Mix
Master
Parts
3D text
Shapes
Logo relief
What I work with
Web & apps
AI
Payments & automation
Hardware & embedded
Desktop & native
Audio & DSP
Proof
Case studies
Engineering suite
SynthLab
Design a synthesizer in the browser: modular patching, schematics, a PCB autorouter with Gerber export, front panels and DSP that compiles to C++.
Seven connected editors, three running free on this site
Open →Automation · payments
Self-delivering shop
On this site: a buyer pays with Stripe and within seconds gets a signed, expiring download link by email. Merch orders go to the printer automatically.
Zero manual steps between payment and delivery
Open →Business app
Faktúry
Invoicing for Slovak businesses: company IDs and VAT handled correctly, Pay by Square QR on every invoice, clients and history saved.
An invoice in under a minute instead of an evening
Private tool, shown on requestE-commerce
Seraphim Customs
Streetwear storefront with product pages, a cart that survives a reload and Stripe checkout on serverless functions.
DEMO SITE: a complete shop you can click through
Open the demo site →Interactive web
Track Park
A browser stage where cats roam and make beats in sync: a small game engine with beat-matched audio loops and importable 'kitten' files.
Turns a music catalogue into something people play with
Open →AI automation
AI helpers
Small AI tools that do one job well: a schematic generator that turns a description into a circuit, a prompt rewriter, and conversation openers.
Proof that a focused AI tool can be built in days
Productivity
Voice Notes
Speak and it becomes a checklist, transcribed in the browser with nothing uploaded, and printable straight onto a Niimbot label printer.
Notes from the field that don't get lost
Hardware, native and desktop
Firmware · iOS · Windows
iPhone → ESP32 screen mirror
Firmware that turns a tiny ESP32-S3 display into a wireless screen: its own Wi-Fi network, a TCP frame protocol, an iOS capture extension and a Windows tray monitor.
Embedded C
PWM audio on a Raspberry Pi Pico
Audio output from a single GPIO pin: a 488 kHz PWM carrier, 22 kHz sample timer and an RC filter, written on the bare Pico SDK.
Browser extension · MIDI
Launchpad Tab Holder
Turns a Novation Launchpad into a hardware tab switcher: each tab claims a lit pad, press it to jump there.
Desktop app · 3D
PrintForge
Desktop app for designing 3D-printable text and shapes, with solid geometry operations and a bundled, tested release build.
C++ audio visualiser
Waveform Tunnel
A 3D tunnel that flies through your audio, built as a C++ plugin and ported to the web; it runs behind the music pages here.
Open →Windows utility
Disk Cleaner
A native Windows app that finds what fills your drive and cleans it safely, built with a proper MVVM structure.
More things I've built
SaaS · live data
TrendPulse
Trend intelligence for entrepreneurs: pulls real signals from Google Trends, App Store charts, GitHub, Hacker News, CoinGecko, npm and more, then turns a signal into a strategy you can act on today.
Ten live data sources in one feed, with accounts and a paid plan
AI · education
Lesson link generator
A teacher uploads a recorded lesson; AI transcribes it with the timing of every word, and the student gets a link where the text lights up exactly as it is spoken.
Listening practice that follows along word by word
Learning platform
Parnas VIP
A members-only learning space: lessons, chat and rooms you can join, sign-up by invite code, in Slovak and English.
Retail tool
Barcode studio
Reads any EAN, UPC or GS1 number (country of origin, check digit), scans from a photo or NFC tag, prints GS1-128 and QR labels, and keeps a library with store, size and price.
Developer tool
Vzhľad Studio
Click any element on any website and restyle it live (colours, fonts, spacing, shadows), then export the CSS or write it straight into your own project. Works through a bookmarklet, even on sites that block embedding.
Acoustics simulator
Soundfield 3D
Shows in 3D where bass builds up in a room: pick a shape or trace your own floor plan, place up to six speakers and a listener, and read the frequency response.
In progress
Reddit post app
An interactive post app on Reddit's own Devvit platform, with a client, a server and its own storage, started as a Reddit companion to TrendPulse.