This year at Microsoft’s developer conference Build in Seattle, mixed reality, Skype video bots, and the Cortana Skills Kit all made headlines, but the work of a Cortana fanboy is getting a lot of attention far from the convention center halls where thousands of Microsoft developers have gathered.

The hologram was made by a software developer who goes by the moniker Unt1tled.

“This is a concept Cortana appliance I’ve built. It’s basically what I imagined Microsoft’s version of Alexa or Google Home would be like if they were to use the holographic AI sidekick from the Halo franchise,” he said in a blog post explaining his build process.

The device was made with a 3D printer, glass, some LEDs, an Arduino chip, and an omnidirectional microphone with the Unity 3D app. Since being uploaded yesterday, video of the Cortana hologram has been viewed nearly 15,000 times.