One of our favorite parts of Hackaday Supercon is seeing all the incredible badge add-ons folks put together. These expansions are made all the more impressive by the fact that they had to design their hardware without any physical access to the badge, and with only a few weeks’ notice. Even under ideal conditions, that’s not a lot of time to get PCBs made, 3D print parts, or write code. If only there was some standard for badge expansions that could speed this process up…

But there is! The Simple Add-On (SAO) standard has been supported by the Supercon badges since 2019, and the 2×3 pin connector has also popped up on badges from various other hacker events such as HOPE and DEF CON. There’s only one problem — to date, the majority of SAOs have been simply decorative, consisting of little more than LEDs connected to the power pins.

This year, we’re looking to redefine what an SAO can be with the Supercon Add-On Contest. Don’t worry, we’re not changing anything about the existing standard — the pinout and connector remains the same. We simply want to challenge hackers and makers to think bigger and bolder.

Thanks to the I2C interface in the SAO header, add-ons can not only communicate with the badge, but with each other as well. We want you to put that capability to use by creating functional SAOs: sensors, displays, buttons, switches, rotary encoders, radios, we want to see it all! Just make sure you submit your six-pin masterpiece to us by the October 15th deadline.

Best of the Best

What’s in it for the winners? Why, nothing short of Hackaday immortality: we’ll put the top SAOs into production and distribute them to each attendee at Hackaday Europe in 2025. Because we actually have to get these things made, entries will have to meet all of the manufacturing requirements outlined on the Hackaday.io page Contest page to qualify.

In addition to a single Best Overall winner, we’ll be picking a top entry for each of the following categories:

• Functional: This challenge is about pushing the envelope for SAOs, so for this category we’ll be looking for the most capable add-on.
• Fine Art: We’ve seen some absolutely gorgeous SAOs over the years, so even though we’re largely pushing for function over form this year, we still want to acknowledge the incredible artistry that goes into them.
• Fun: It’s not all about business. SAOs are often a bit tongue in cheek, with many referencing online memes or parts of hacker culture. If you want to win in this category, you’ll need to lighten up a bit.

Honorable Mention

We know this community too well to believe you’ll all stick to the predefined categories, so as usual in our contests, we’ll be keeping an eye out for entries that best exemplify the following Honorable Mention categories.

• Coolest Toys: We’re suckers for interesting parts, so the SAO selected for this category will be the one with the most unique or impressive electronic components onboard.
• Light Show: We want to challenge the idea that SAOs are just for blinking LEDs, so naturally, at least one of you is going to go against the grain and add as many LEDs as possible.
• Most Ambitious: Sometimes, it’s the thought that counts. Whether or not the final product worked as expected, the SAO selected for this category will be the one that took the biggest swing.
• Best Communication: Getting SAOs to talk to the badge and each other is what this contest is really all about, so we’re looking for the one example that really ran with the concept.
• Least Manufacturable: SAOs often employ design or assembly hacks (like mounting LEDs upside-down) that don’t scale well. In this category we’re looking for hand-crafted masterpieces. To quote Hunter S. Thompson, “A high-powered mutant of some kind never even considered for mass production.”

A Little Inspiration

There’s no shortage of gorgeous SAOs out there already, just search Hackaday.io or Tindie, and you’ll come up with dozens of badge add-ons that you didn’t even know you needed until right now. But as for examples of functional SAOs that do more than just blink LEDs…that’s quite a bit harder. We weren’t joking when we said they’ve been quite rare so far.

But we can point you towards a couple resources that should help you get started. Our own [Arya Voronova] wrote up her tale of creating a Jolly Wrencher SAO back in 2022 that goes over the basics, and we’d also recommend taking a look at her ongoing “I2C for Hackers” series of articles if you need to brush up on the communication side of things. If you need some pointers on the artistic front, you can’t go wrong following in the footsteps of [TwinkleTwinkie]. His Supercon 2019 talk PCB Art is Pain is a fantastic look at pushing the envelope of PCB design and production, and his Hackaday.io post about backlighting board art is required reading around these parts.