The Volt library

Fine-grained signals, two authoring styles, one ~260-line file. Not React: no JSX, no virtual DOM — reading a signal subscribes that exact piece of UI; writing touches only the text/attribute that changed.

import { signal, computed, effect, el, html, mount } from "/volt.js";

const n = signal(0);                  // n() reads, n(next) writes
const even = computed(() => n() % 2 === 0);
effect(() => console.log("n is", n()));

const view = el("button", { onClick: () => n(n() + 1) }, () => String(n()));
const card = html`<p>${n} is ${() => (even() ? "even" : "odd")}</p>`;
mount("#app", view, card);

• signal(initial) — getter/setter function.
• computed(fn) — read-only derived signal.
• effect(fn) — runs fn, re-runs on change; returns a disposer.
• el(tag, props?, ...children) — a DOM element; function props/children are live.
• The html tagged template — ${signal} holes, onclick=${fn}, value=${signal}.
• mount(target, ...children) — append into a selector/element.

Interpolated values render as text nodes (HTML-escaped) — user content can't inject markup.