1. First Web App (Vite)

To create your first application, it is better to use vite. Fast build under prod, and support for typescript during development

Creating project Vite

We'll use the vanilla-ts template

npm create vite@latest horizon-app -- --template vanilla-ts

Go to the directory

cd horizon-app

Install dependencies

npm i;
npm i horizon-core

Prepare project

Go to src/main.ts and edit file

import { defineApp } from "horizon-core";
import { comp } from "horizon-core/component";
import { useSignal } from "horizon-core/state";

const app = defineApp()

const mainComponent = comp((_, { text, $ }) => {
    const counter = useSignal(
        0, { asRaw: value => `Counter: ${value}` }
    )

    $('button', {
        '@click': () => counter.value++
    }, () => {
        text(counter)
    })
})

mainComponent.composable.dom = document.body.querySelector('#app') 
    ?? document.body

app.renderDOM(app, mainComponent)

Launch Dev

npm run dev

Launch Prod

npm run build;
npm run preview

see also Creating component