Ismael Manzano /
Full Stack Developer

Full stack development with technical judgment: maintainable systems built to last. Available for new projects.

The person behind leo/

|My pathI'm 21, I've just finished my studies in Multiplatform Application Development. I didn't have much clarity at first, but over time something changed: I stopped learning patterns and started understanding why things exist. Most of what I know I learned on my own: testing, breaking systems, reading documentation at 3am, fixing errors with no one telling me "this is right."

|Where leo/ comes fromleo/ comes from my surname, León. The slash comes from the terminal: if you've spent time on a command line, you recognize the prompt. It felt like a good way to sum up how I work, from the ground up and with my own judgment.

|How I workI take responsibility for everything I build, from architecture to production. If something breaks, it's on me, and I prefer it that way. I move at a good pace but without shortcuts, because there's a difference between code that works and code that's well built.

Ismael Manzano LeónFull Stack Developer

Experience

Companies I've worked with.

Feb 2026 — May 2026

ENTREREDES CONSULTORÍA TECNOLÓGICA

Full Stack Developer

Dual Vocational Training · Ciudad Real

Solo development of a landing-page generator SaaS (Laravel + Filament PHP), shipped to production with Docker and Gemini AI integration via async Jobs.

LaravelFilament PHPGemini AIPHPUnitDockerPHP

Mar 2025 — Apr 2025

Savia by Berger-Levrault

Frontend Software Developer

Dual Vocational Training

Frontend application with React 19 and Vite: managing 1000+ records with instant search, multi-filter, local persistence and reusable components with high-performance animations.

ReactViteJavaScriptTypeScriptGit

Feb 2025

Cojali S.L.

Software QA Analyst

Dual Vocational Training

Implementation of an internal technical survey system for personnel evaluation, along with functional testing and quality assurance processes in the development cycle.

Clean CodeQATestingPHPUnit

Systems

What I build.

Production

DevConsole

Command dispatcher decoupled from the renderer. A composable useTerminal as an injectable reactive state machine without touching the DOM. Virtual filesystem, ghost-text autocomplete with real-time prefix matching, i18n lazy-loaded from external JSON with zero bundle impact, demo mode with async orchestration via Typed.js.

Vue 3ViteTyped.jsTailwind v4

View case study→

Production

Kairos

Flutter app + FastAPI backend + Google Gemini. Turns task abandonment into quantifiable debt. AI-generated stoic reflections, real-time geofencing, tunnel vision with automatic time-blocking. No randomness in the tracking.

FlutterFastAPIGoogle GeminiPostgreSQL

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Production

PokeCore

React 19 + Vite. 1,025 Pokémon with instant search, type filtering (18 types), persistent favorites in localStorage, glass modal with animated stats, shiny sprite toggle, weaknesses and evolution chain. Fully localized, mobile-first responsive.

React 19ViteTanStack QueryFramer Motion

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In development

Regicide

A pure strategy game with perfect information and no unfair RNG. A state machine with four phases (attack, defense, broken balance, end) where every decision has predictable consequences.

Game DesignState MachineStrategy

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