Looking at the specs of the Teensy 4.0 sent me back to my time in Akihabara, Japan circa 1999. Polished CD players catch the sun in every main street shop window, but just a block into the backstreets crowded bins of raw electronic parts line the shops. From a barely-advertised store I catch a glimpse of a Silicon Graphics workstation, a powerhouse of a computer with a price tag in the tens of thousands. Next to it, someone has overclocked a Pentium desktop to 600MHz. 600MHz! In another cycle of Moore’s law, we’ll have to start talking in GHz.

With a 600MHz clock speed, the Teensy 4.0 has horsepower beyond anything we’re used to seeing in the microcontroller space. And they’re going for $19.95, a price competitive with mainstream microcontrollers.

The NXP proc at the heart of Teensy 4.0 brings a smattering of other features uncommon in hobby microcontrollers: A CAN bus for communicating with automotive electronics, audio output, and processing for graphics and encryption like we’d normally expect to see on a single board computer rather than a microcontroller.

In many ways this is a stripped down board. It comes without headers; it’s your choice to solder on whatever pins you like, or wire your project directly to the PCB. Documentation on the board is a hefty dose of technical detail, straight from the designer to you, rather than a polished step-by-step tutorial. First-time makers may want to seek a board built with beginners in mind, but for makers with a few projects under their belt, the Teensy 4.0 packs the horsepower of a Y2K desktop at a price that matches boards with less than a tenth of this horsepower.