Welcome to Stockfighter.

StockFighter is a free Capture The Flag (CTF) programming challenge by Patrick, Erin, and Thomas at Starfighter.

You don't need to understand anything about CTFs, microcontrollers, security, or trading to participate. In fact, it's more fun if you don't!

Starfighter is a weird new kind of recruiting firm. Instead of spamming people, we meet people by making programming challenges.

You do not need to be looking for a job to participate! Most people who participate won't be.

Forgot password?

Not playing yet? It's free.

We'll never share your information without your permission.


Stockfighter Jailbreak is a CTF about breaking the security of an AVR device.

┌───────────────────────────────────────────┐
│                                           │
│                                       ◐   │
│                                           │
│                                           │
│ ┌────────────────┐┌───┐┌───┐   ┌───┐┌─┬─┐ │
│ │      FCOJ      ││ $ ││ # │   │ # ││ │ │ │
│ └────────────────┘└───┘└───┘   └───┘└─┴─┘ │
│ ┌────────────────┐┌───┐┌───┐   ┌───┐┌─┬─┐ │
│ │      FCOJ      ││ $ ││ # │   │ # ││ │ │ │
│ └────────────────┘└───┘└───┘   └───┘└─┴─┘ │
│ ┌────────────────┐┌───┐┌───┐   ┌───┐┌─┬─┐ │
│ │      FCOJ      ││ $ ││ # │   │ # ││ │ │ │
│ └────────────────┘└───┘└───┘   └───┘└─┴─┘ │
│ ┌────────────────┐┌───┐┌───┐   ┌───┐┌─┬─┐ │
│ │      FCOJ      ││ $ ││ # │   │ # ││ │ │ │
│ └────────────────┘└───┘└───┘   └───┘└─┴─┘ │
│ ┌────────────────┐┌───┐┌───┐   ┌───┐┌─┬─┐ │
│ │      FCOJ      ││ $ ││ # │   │ # ││ │ │ │
│ └────────────────┘└───┘└───┘   └───┘└─┴─┘ │
│                                           │
│ ┌──────────────────────────────────────┐  │
│ │██████████████████████████████████████│  │
│ │██████████████████████████████████████│  │
│ │██████████████████████████████████████│  │
│ │██████████████████████████████████████│  │
│ │██████████████████████████████████████│  │
│ └──────────────────────────────────────┘  │
│                                           │
└───────────────────────────────────────────┘

So, there's this market. And, connected to the market, there's these hand-held trading devices.

The people who run the market issue them to traders.

They're thinking, like, traders trade. They don't code. They don't take things apart. They're not going to do anything weird with these devices.

And so the market trusts the handheld devices.

Probably they shouldn't. Turns out...

We've taken apart the devices for you. Figured out a bit of how they work.

We wrote you a debugger.

We got a compiler working for it. We can load code onto it.

Some code. Not anything we want. Not yet. The market is starting to catch on. They're burning our bugs.

Ten levels. Ten versions. Ten tries to keep you out.

If you're interested, here's a chance to: mess around with low-level AVR architecture. Exploit memory corruption flaws. Reverse engineer code in multiple architectures. Bypass encrypted-code content protection. Break out of an interpreter environment.

Without leaving your browser.

Start Playing
                               ┌ ─ ─ ─ ─ ─ ┐
                               │    RF     │
                               └ ─ ─ ─ ─ ─ ┘
                                     ▲      
                                     ▼      
╔═══════════╗   ╔═══════════╗  ╔═══════════╗
║ mystery   ║   ║ app       ║  ║ network   ║
║ avr       ║   ║ avr       ║  ║ avr       ║
║           ║   ║           ║  ║           ║
╚═══════════╝   ╚═══════════╝  ╚═══════════╝
      ▲               ▲              ▲      
      └───────────────┼──────────────┘      
                      ▼                     
             ┌ ─ ─ ─ ─ ─ ─ ─ ─              
             │ i/o controller |              
             └ ─ ─ ─ ─ ─ ─ ─ ─              
                      ▲                     
             ┌────────┴───────┐             
             │                │             
             ▼                │             
       ┌───────────┐    ┌ ─ ─ ─ ─ ─ ┐       
       │           │    │           │         
       │ flash     │    │ interface │       
       │           │    │           │         
       └───────────┘    └ ─ ─ ─ ─ ─ ┘       


Stockfighter Trading is a CTF about automated trading.

laptop

Start playing now; no experience required.

We'll take you on a quick crash-course around the ventilation ducts of a stock exchange. You'll learn how an order book works, how market making works, and what a block order is. You'll write code (in your language of choice) to do stock trading against our REST API.

You'll have a blast, and not cause a global financial crisis. Well, probably.

Start Playing

Realistic simulated market

Challenges are designed against a backdrop of real, shared limit order book markets. You trade fictional stocks in a market populated by algorithmic traders making real fake trades.

REST API for trading

Participants design, test, and compete with market-making algorithms using a simple JSON/RPC API. It is extensively documented; 50+ OSS libraries exist. Use any you like or write your own in any language.

HFT/Anti-HFT

Play cat-and-mouse against market-making algorithms by efficiently trading large blocks of stock without getting sniped by predatory tradeers.

Fraud Detection

Build algorithms to detect patterns and anomalies in large volumes of trading information.

Security Research

Ever wanted to hack a stock exchange without going to jail? Try to exploit our API and/or rig the markets.

Thriving Community

We've got forums (and a public unofficial Slack) where our players hang out. If you want help on programming or on particular challenges, feel free to ask. Our community is friendly, helpful, and responsive.

Starfighter

Starfighter is a new, weird kind of recruiting company. We detect and market underpriced programming talent. We do that by creating opportunities for programmers to casually and effectively demonstrate aptitude.

Also, we just like designing programming challenges.

© 2016 Ketchup Salt, LLC