ES
Independent developer · Spain · Remote

Software, AI automations and Roblox games, built with care.

Desktop and web apps, assistants that act on voice and plain language, and original Roblox games. Each one designed, built and shipped end to end.

Start a commission See the work
Softwaredesktop and web apps, APIs
AIagents, voice assistants and bots
Robloxoriginal games and systems

WorkSelected work

Software and automation projects, from a desktop app with an offline mode to an inventory you can run by voice.

Software

ClockiFree

Time tracking, timesheets and invoicing for teams, on desktop and the web.

DesktopWindows app with offline modeWebinstallable PWA and REST API
Laravel 12PHP 8.2React 19TypeScriptVite
View project GitHub
Voice Inventory — Illustration
You “Alexa, ask the warehouse how many 40 mm hinges are left.”
Action stock.lookup { sku: "HNG-40", location: * }
Alexa “There are 312 in aisle 4, shelf B, and 60 in returns.”
You “Move 50 from returns to aisle 4.”
Action stock.move { sku: "HNG-40", qty: 50, from: "RET", to: "A4-B" }
Alexa “Moving 50 hinges from returns to aisle 4, shelf B. Shall I confirm?”
You “Yes.”
Alexa “Done. Aisle 4 now has 362.”
AI & automation

Voice Inventory

Warehouse inventory you run by talking: stock checks, movements and counts, hands-free.

Hands-freeno screen or scanner needed< 8 sper answer, inside Alexa's window
Alexa Skills KitNode.jsAWS LambdaOpenAI function callingREST API
View project
CordAI — Illustration
You /cordai “Create a support category with a tickets channel only moderators can see”
Action createCategory("Support") → createChannel("tickets") → setPermissions(@everyone: deny, @Moderators: allow)
Bot Created Support › #tickets. Hidden from everyone except Moderators.
AI & automation

CordAI

A Discord bot that turns plain requests into real server changes, by chat, by voice or from an AI coding agent.

3ways in: chat, voice, MCP1 €monthly hosting cap
Node.jsdiscord.jsOpenAI function callingModel Context ProtocolAlexa Skills Kit
View project
All projects (6)

RobloxRoblox games

Original games published under Starshade. Everything from systems and UI to monetisation and live updates.

2 published games Starshade

GitHubOpen source

Code you can read, run and fork. New repositories land here as they are published.

j4tz/clockifree

Time tracking, timesheets and invoicing for teams, on desktop and the web.

Laravel 12PHP 8.2React 19TypeScriptViteTailwind v4
View project
github.com/j4tz Follow on GitHub

ServicesWhat I can build for you

Software development

Desktop and web applications, REST APIs and internal tools, built to be maintained after launch.

  • Desktop apps (Electron) with auto-update
  • Web apps and PWAs (React, Laravel)
  • REST APIs, webhooks and integrations
  • Dashboards, reports and invoicing

AI automation

Assistants that do the work instead of just answering, connected to the tools a team already uses.

  • AI agents with function calling
  • Voice assistants and Alexa skills
  • Discord bots and MCP servers
  • Workflow automation between services

Roblox development

Complete games or the parts you need: gameplay, data, UI and live operations.

  • Full games from concept to launch
  • Data stores, economy, shops and quests
  • UI, onboarding and mobile support
  • Luau or roblox-ts, with Rojo and Git

How a commission works

  1. Brief

    You tell me what you need. I come back with questions, a scope and a fixed quote.

  2. First version

    An early build you can click through or play, so we agree on direction before the details.

  3. Build

    Regular builds you can try, with short notes on what changed and what comes next.

  4. Handover

    Launch, documentation and the source code. Support afterwards if you want it.

Also built

Browser extension for Roblox

A Chrome (MV3) extension that adds item values, UGC data and quality-of-life tools to the Roblox website.

Minecraft server plugins

Custom Paper plugins for a community server: world generation, custom mobs and bosses, combat and a lobby with mini-games.

Roblox Studio tooling

A Studio plugin that connects to Rojo by itself, and a scripted pipeline that builds a 140-piece low-poly asset pack.

Contact

Have something in mind?

Tell me what you want to build, roughly when you need it, and any links or references that help. I will reply with questions or a quote.

hello@j4tz.com
Emailhello@j4tz.com GitHubj4tz Roblox groupStarshade