The working copy, powered on.

edit the file below — the actual Pyxle parser and real CPython re-run it in this tab

CPython via Pyodide · ~12 MB once⌘/Ctrl + Enter — run nowyour first edit boots the runtime

@action + state

counter.pyxledit me — your first edit boots CPython

# counter.pyxl
 
# Count lives in Python. The @action
# mutates it on the server (sandboxed here).
count = 0
 
@server
async def load(request):
    return {"count": count}
 
@action
async def increment(request):
    global count
    count += 1
    return {"count": count}
 
 
import React, { useState } from 'react';
import { useAction } from 'pyxle/client';
 
export default function Counter({ data }) {
    const [count, setCount] = useState(data.count);
    const increment = useAction('increment');
 
    async function bump() {
        const res = await increment();
        if (res.ok) setCount(res.count);
    }
 
    return (
        <div className="card">
            <span className="tag">state lives in Python</span>
            <h1>{count}</h1>
            <p>Each click runs the @action — real Python.</p>
            <button onClick={bump} disabled={increment.pending}>
                {increment.pending ? 'Running…' : 'Increment +'}
            </button>
        </div>
    );
}

resultplain JS until you edit

state lives in Python

0

Edit the code → real Python boots.

sandbox log · boots, runs, errorsidle

— opens on your first edit

sandboxed iframe · opaque origin · no cookies, no page DOM — in a real app the Python half runs server-side on Starlette; here CPython stands in for the server

02 · Server

This board hits this page’s real @action.

every tap is an HTTP POST to the handler printed alongside — counts persist in SQLite on this server · 97,545 page loads so far, same database

react to this page129 total

request logreal HTTP · this server

— opens on your first tap

pages/playground.pyxlruns on this server

@action
async def react_emoji(request):
    from db import check_rate_limit, get_client_ip, increment_reaction
 
    client_ip = get_client_ip(request)
    # 5 reactions per hour per IP, scoped to the playground reactions board.
    if not await check_rate_limit(client_ip, scope="react_emoji"):
        raise ActionError(
            "Rate limit reached. Please try again after 1 hour.",
            status_code=429,
        )
 
    body = await request.json()
    emoji = body.get("emoji", "")
    if emoji not in VALID_EMOJIS:
        raise ActionError("Invalid reaction", status_code=400)
 
    new_count = await increment_reaction(emoji)
    return {"ok": True, "emoji": emoji, "count": new_count}

03 · Start

Run it for real.

the same anatomy on your machine — the homepage terminal replays a real session

Docs the captured session →GitHub

v0.9.4 on PyPI · MIT