Stock Market Challenge

This challenge drops you into a trading terminal for a single fictional stock, ACME. The moment you start, your account holds $10,000 in cash and ACME's price begins ticking in real time on a live chart. Two buttons — Buy and Sell — are all you get: Buy commits your entire cash balance to shares at the current price, Sell converts your entire share position back to cash. There's no quantity field and no short-selling; the only decision is when.

The goal is simple to state and hard to execute: grow your net worth — cash plus the value of any open position — to 101% of what you started with, then click Cash Out to lock it in and finish the run. Cash Out stays disabled until you've actually cleared the target; there's no partial credit for coming close.

What this tests

ACME's price updates several times a second and swings hard enough that a human clicking by eye will struggle to land a profitable trade before the moment has passed. This isn't a test of trading strategy — it's a test of your automation tool's read-react loop: how fast can it read a DOM value, evaluate a condition, and fire a click, in a loop, without falling behind.

Try it with

A script polling #acme-price on a tight interval (every 50-100ms is a reasonable starting point) and clicking Buy or Sell based on whatever threshold logic you choose; RPA tools with fast reaction loops; anything that can act on a changing value faster than human reflexes allow.

Tips

Watch the Cash / Shares / Net Value row under the chart — Cash Out only lights up once Net Value has actually cleared the 1% target. Append ?seed=42 to the URL for a repeatable price series while you build and test your automation. A Restart button resets the round at any time if you want to try a different approach.