One of Snap’s (SNAP) former employees thinks its augmented reality glasses are "bad."

Sterling Crispin, an engineer who worked on designing previous versions of the glasses, slammed the product in a post on X, formerly known as Twitter, this week.

“I worked on these for about a year at Snap, and I have a million negative things to say about the experience and the device,” Crispin wrote of Snap’s AR Spectacles, “but I think the product speaks for itself and is obviously bad.”

Snap did not immediately respond to Yahoo Finance’s request for comment.

“I don’t want to get into the specifics because I might inadvertently break an NDA and would probably hurt some people’s feelings who worked on it, but it’s really a disaster,” Crispin continued.

Crispin was laid off from Snap in 2022, according to a LinkedIn post he shared at the time.

Snap's newest AR Spectacles represent a bid to expand in a struggling market. Meta (META) has lost nearly $50 billion in the more than four years its Reality Labs division has spent developing its AR and VR products. Apple’s (AAPL) attempt to best the market with its uber-expensive Vision Pro headsets has disappointed consumers and investors alike. Not to mention the failures of Google Glass (GOOG) and Microsoft’s HoloLens (MSFT), among others.

But that hasn’t stopped Meta, Apple, and now Snap from trying. Meta and Ray Ban-parent EssilorLuxottica (ESLOY) recently expanded their partnership as they continue to work on creating AI-enabled Ray Ban smart glasses. Apple opened up Vision Pro sales abroad this summer, and the product was heavily highlighted during Apple’s Worldwide Developers Conference in June. And Google, Qualcomm (QCOM), and Samsung (005930.KS) are reportedly working on smart glasses too.

Snap isn’t exactly new to the space. The company first launched its Spectacles in 2016 and added augmented reality features to the glasses in 2021, though those features were only available to about 200 creators. Its fifth-generation Spectacles debuted this week — this time as an AR product for a wider audience. The product will be available as part of the company’s developer kit for $99 a month.

“Spectacles are the result of a decade of research and development to introduce hardware that breaks the bounds of screens and brings people together in the real world,” the company said in its announcement Wednesday.

The glasses have gotten mostly positive feedback. MIT Tech Review said the Spectacles “could finally deliver on the promises devices like Magic Leap, or HoloLens, or even Google Glass, made many years ago.” A CNET review said, “Snap is getting a foot in the door a little ahead of competitors.” The Verge said Snap is getting closer to creating “compelling AR.”