Tiny mandelbrot renderer. `npm install pngjs-image` then run with `node tiny.js`

tiny.js

const MIN = { x: -2, y: -1 }, MAX = { x: 1, y: 1 };
const WIDTH = HEIGHT = 1000;

function getEscapeCount(c) {
  let z = { a: 0, b: 0 };
  for (let i = 0; i < 100; i++) {
    if (Math.pow(z.a, 2) + Math.pow(z.b, 2) > 4) return i;
    z = { a: Math.pow(z.a, 2) - Math.pow(z.b, 2) + c.a, b: z.a * z.b + c.b };
  }
}

let image = require('pngjs-image').createImage(WIDTH, HEIGHT);
for (let y = 0; y < HEIGHT; y++) {
  const fractalY = MIN.y + ((MAX.y - MIN.y) / HEIGHT * y);
  for (let x = 0; x < WIDTH; x++) {
    const fractalX = MIN.x + ((MAX.x - MIN.x) / WIDTH * x);
    const value = getEscapeCount({a: fractalX, b: fractalY}) == null ? 255 : 0;
    image.setAt(x, y, { red: value, green: value, blue: value, alpha: 200 });
  }
}
image.writeImage('./out.png');

Node that the fractal rendered by this will look a little off due to the limits of JS number precision. Swap out all the math with https://github.com/MikeMcl/bignumber.js to make it look right.