(CNN) A developer who spent three years helping create Google+ has written a brutal blog post declaring the tech giant's social network a failure. In a lengthy, at times profane breakdown on blogging platform Medium, Chris Messina, the man credited as inventor of the hashtag, writes that Google missed a chance to make the service a one-stop home for its users' online identities and, instead, created a less-popular Facebook copycat. "Lately, I just feel like Google+ is confused and adrift at sea," Messina wrote. "It's so far behind, how can it possibly catch up?" The November 28 post was a follow-up to a tweet in which he had mistakenly called out a bug on Google+ that was actually caused by an external app. Even as he corrected himself, he called out Google for the network's missed opportunity.
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Former Google+ developer says the social tool has failed
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Hashtag inventor Chris Messina left Google over a year ago
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He says G+ could have been about identity, became "Facebook lite"
"The future of digital identity should not be determined by one company (namely, @placeholder)," he said.