scastarnado

Sergi Castarnado
Software developer building useful tools, developer-facing products, desktop systems, and interactive software.
I work across the stack—from APIs, data models, authentication, and real-time systems to polished web interfaces, Windows utilities, and game prototypes.

Barcelona, Spain · Software Engineering · Full-stack, backend, desktop, and games

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Engineering profile

I am a software developer and Computer Science student focused on turning ideas into complete, usable systems. My strongest work sits at the intersection of backend-heavy full-stack development, developer and productivity tooling, desktop automation, and interactive software usually based on my needs or things that would help me in some way.

My current technical direction is deeper software engineering: maintainable architecture, reliable/intuitive/secure APIs, automation, algorithms, and game/engine development.

Selected work

DocuForge
Developer-focused HTML-to-PDF platform structured as a monorepo, with a Hono API, Next.js dashboard, Playwright rendering, reusable templates, PostgreSQL/Redis infrastructure, and TypeScript and Python SDKs.
TypeScript Hono Next.js Playwright PostgreSQL Redis








AmaiOS
A modular operating-system simulation running entirely in the browser. Includes a window manager, taskbar, start menu, persistent virtual file system, terminal, code editor, paint app, games, and other desktop applications.
Live demo
JavaScript HTML CSS ES Modules localStorage










ClickityClackityCloom
A Windows automation utility with configurable clicking, global hotkeys, fixed-coordinate targeting, macro recording and playback, JSON persistence, import/export, localization, and distributable releases.
C# .NET Framework WinForms Windows Hooks JSON








ClickityStrokittyCloom
A customizable Windows keystroke visualizer for developers, educators, and streamers. Supports global input capture, key combinations, profiles, per-app filtering, tray controls, JSON import/export, and executable/installer builds.
Python Desktop UI Global Input Hooks PyInstaller PowerShell










Game Systems Lab
A collection of Unity and interactive-system experiments covering tower defense, platforming, RPG and FPS mechanics, input, progression, NPC behavior, UI systems, and gameplay prototyping.
Unity C# Game Architecture Gameplay Systems Prototyping

Technical stack

Primary

!TypeScript
!JavaScript
!React
!Next.js
!PHP
!Laravel
!C Sharp
!Python

Platforms, data, and tooling

!Node.js
!PostgreSQL
!MySQL
!Supabase
!Tailwind CSS
!Docker
!Git
!GitHub Actions
!Unity
!Linux

GitHub analytics dashboard

Contributions, commits, pull requests, issues, and stars

Language distribution

These cards measure public repository composition and commit distribution. They are not a direct proficiency ranking.

Current streak, longest streak, and total contributions

Contribution activity graph

Repository telemetry

The badges below update automatically from GitHub and show the health and adoption signals of the repositories most relevant to users and employers.

| Project | Adoption | Maintenance | Distribution |
|---|---|---|---|
| DocuForge | !Stars !Forks | !Issues !Last commit | !License !Repo size |
| AmaiOS | !Stars !Forks | !Issues !Last commit | !License !Repo size |
| ClickityClackityCloom | !Stars !Downloads | !Issues !Last commit | !Release !License |
| ClickityStrokittyCloom | !Stars !Forks | !Issues !Last commit | !License !Repo size |

Selected build milestones

| Milestone | Engineering evidence |
|---|---|
| Built an OS-like environment in the browser | Modular applications, window lifecycle management, virtual file persistence, terminal commands, editors, settings, and games. |
| Designed an API product rather than a single app | Monorepo boundaries, rendering service, dashboard, database and cache infrastructure, documentation, and multi-language SDKs. |
| Worked with system-wide desktop input | Global mouse/keyboard hooks, hotkeys, foreground-process filtering, macro timing, profiles, and local persistence. |
| Applied privacy controls at the data layer | User-scoped PostgreSQL rows, tags, relationships, and private object-storage paths through Supabase policies. |
| Built across multiple software surfaces | Browser applications, APIs, Windows d

…

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