SquirrelFish's bytecode engine elegantly eliminates almost all of the overhead of a tree-walking interpreter. First, a bytecode stream exactly describes the operations needed to execute a program.

To solve this problem, he created Espruino, a JavaScript interpreter for the new batch of ARM development boards that have been cropping up.

This interpreter runs on dozens of different microcontrollers, but being the latest, greatest, and most popular new microcontroller platform means a new solution for the ESP is very, very exciting.

The new Mozilla JavaScript interpreter is also about 2.4 times faster than the newest interpreter slated for Apple Inc.’s Safari, according to benchmark tests.

The Espruino Pico is a USB stick that is equipped with a tiny computer and integrated JavaScript interpreter, allowing for instant feedback from whatever device you’re working with.