# [Cubix], 7 bytes

    w>O@D1.

Outputs 0 with 1/3 probability, 1 with 2/3 probability. [Try it online!]

I think this is the first time I've had to pad the source code with no-ops to make the cube the correct size...

### Explanation

Cubix is a 2D stack-based esolang wrapped around a cube. The source code won't fit onto a size-1 cube, and so it gets wrapped around a size-2 cube, with the following cube net:

        w >
        O @
    D 1 . . . . . .
    . . . . . . . .
        . .
        . .

The IP (instruction pointer) is then sent into action, starting at the top-left corner of the left-most face, and facing easy. The first instruction it hits is `D`, which points the IP in a random direction. This isn't the best possible source of randomness for this challenge, but it's the only one Cubix has.

If the IP is pointed north, it wraps onto the `w` on the top face, which moves the IP one position to the right (south at this point). `O` outputs the top item on the stack as a number (`0` if the stack is empty), and `@` ends the program.

If the IP is pointed south, it wraps around various faces before hitting the `>` on the top face. It's going west at this point, and `>` points the cursor east, sending it back to the `D`, which starts the whole process over.

If the IP is pointed east or west, it simply wraps around the third row of the above diagram, hitting the `1` at some point in the middle. When it gets back to the `D`, the process is started again as before, but when the IP eventually gets sent north, `O` outputs `1` instead of `0`.

So each time `D` is hit, there's a 2/4 chance that the output will be `1`, and a 1/4 chance that it will be `0`. The other 1/4 is simply the chance of the process starting over, and so if we sum the infinitely shrinking chances of each output, we get 2/3 for `1` and 1/3 for `0`.

[Cubix]: https://github.com/ETHproductions/cubix
[Try it online!]: https://tio.run/nexus/cubix#@19u5@/gYqj3///XvHzd5MTkjFQA "Cubix – TIO Nexus"