SPOILER ALERT These are my solutions for StockFighter. Feel free to take a look at them and offer critique/suggestions/advice/whatever, but just be aware that if you do not want to see spoilers for StockFighter, do not look at this code.

I wrote a nifty PHP library that I use in this code, and that can be found (with no spoilers!) here.

To install my solution set (and use them toward your own StockFighter account), you'll need to follow these steps:

composer install # Install composer dependencies.
cp config/api.json config/api.local.json # Create your configuration file.

Then, add your API key to config/api.local.json. Once you've done that, you should be ready to launch the application:

chmod a+x ./stockfighter
./stockfighter

The help screen will show you how to use each level command. Each level has arguments for the items that change (account number, stock, venue, etc).

My solutions for each level certainly aren't the best (no one is perfect, of course!), so here are my comments on my implementation for each level:

On this level, I tried to first brute-force it and order 1000 shares at a time, spreading them apart by 10 seconds or something like that. Of course, that didn't work because I had no idea what the price was when I was making the purchase.

I ended up adopting an approach that monitored the WebSocket connection for the current quote for the stock in question, and then bought once it went below a specific threshold (the last purchase price of the stock at the beginning of execution plus $1.00 padding). That seemed to work for my case, though it failed the first time around (I was initially using the ask price instead of the last price, so that might have something to do with it). If it doesn't work for you the first time, try, try again!

I'll also clean up the code for this level once I use it in some other levels :)