hedron-sim

Offline HTMX simulation for Hedron docs and demos.

Author demos with ordinary Hedron components (Page, RefreshButton, swap, regions), then embed them in static docs. A small JavaScript runtime intercepts hx-* attributes and serves pre-rendered fragment HTML — no FastAPI process required.

Package maturity: Beta tooling-grade (0.2.x) · pin >=0.2.0,<0.3

Install

pip install "hedron-sim>=0.2.0,<0.3"
# or
uv add "hedron-sim>=0.2.0,<0.3"

Requires Python 3.10–3.14 and hedron (for component imports used in demos).

Quick start

from hedron import Page, RefreshButton, Stack, Text, html, swap
from hedron_sim import SimApp, embed_demo, sim_utc

app = SimApp(demo_id="hello-status")
status = app.region("service-status")


def status_panel():
    return html.div(
        Text(f"All systems operational · refreshed {sim_utc()}"),
        id=status.id,
        role="status",
        aria={"live": "polite"},
    )


@app.page("/")
def home() -> Page:
    return Page(
        Stack(
            Text("Hello from hedron-sim"),
            status_panel(),
            RefreshButton.for_region(status, href="/status", label="Refresh status"),
        ),
        title="Demo",
    )


@app.fragment("/status", region=status)  # SimApp package-native simulator route
def refresh_status():
    return swap(status_panel())


print(embed_demo(app))

Ship static assets

from pathlib import Path
from hedron_sim.assets import copy_assets

copy_assets(Path("docs/javascript"), Path("docs/stylesheets"))

Then load hedron-sim.js (and optionally hedron-sim.css) from MkDocs extra_javascript / extra_css.

Public API

Links

• Package docs
• Documentation
• Changelog
• Source
• Issues
• hedron

License

MIT. See the repository license.