It’s been a whirlwind year for China’s internet culture — from trade wars and a huge vaccine scare, to a rise in feminist activism through social media. All along the way, authoritarianism has also been on the rise there, as the nation’s internet regulator imposes new rules on what’s banned, from Twitch getting shut down, to removing parodies and even ASMR videos.

Yet 2018 is most notable for being the year that Chinese internet users got away with significantly more than they ever have in the past, however small or short-lived those victories might be. Thanks to the blockchain, this year users managed to preserve censored information in ways that thwarted the government’s fast-growing censorship efforts. In April, student activists posted a #MeToo open letter — written by a student who had been threatened by her college not to discuss sexual assault — into the metadata of an Ethereum blockchain transaction. Then, in July, the blockchain was used again as citizens collectively fought to preserve an investigative story that exposed how Chinese babies were being given inferior vaccines.

Generally, Chinese citizens avoid publicly commenting on political issues, turning a blind eye to societal affairs they don’t have control over anyway, out of fear of retribution from the Cyberspace Administration of China. But both cryptographically preserved incidents struck a nerve. In a country where many still only have one child, the vaccine scandal was a source of anger and frustration, as it involved hundreds of thousands of faulty vaccines mostly given to babies. And for countless women across China, attention turned toward domestic abuse, sexual harassment, and even rape, started a firestorm that even the warnings of authority figures could not stem.

Both posts contained damning evidence the government doesn’t want shared: the open letter reveals that a student was detained and had her family’s safety threatened over a freedom of information request she had helped to submit to shed light on the case of another woman at the school who committed suicide in 1998 after being allegedly raped by a former professor. The vaccine article reported that a Shenzhen-based biotech company gave babies inferior vaccines that failed to combat whooping cough and tetanus, just for the sake of increasing profit margins.

The stories revealed an uglier side of China that the internet regulating body has taken many pains to hide, especially under the reign of President Xi Jinping, who has worked to solidify his power and abolished term limits in March, meaning he can rule until death.

Social media posts featuring sensitive keywords are often taken down, and users who share photos with sensitive imagery often have their posts blocked. But even after censors have taken down all other attempts to spread these articles via social media, the posts remain publicly available as transactions logged on the blockchain’s public ledger. Because they’re pasted into the metadata of transactions, each roughly totaling a few US cents, the posts are hard to tamper with; as blockchain is decentralized, Beijing monitors have also been unable to pressure network owners into removing them.

Blockchain experts say it would be challenging, if not downright impossible, to retroactively censor these embedded messages. “The Chinese government cannot remove those posts,” says Coin Center’s director of communications Neeraj Agrawal. “They will live on the Ethereum blockchain forever.”

The loophole takes advantage of a nascent technology that state authorities have quietly approved. Although China has banned cryptocurrency from being traded — a decision that has impacted many companies, even causing some to leave the country — the underlying blockchain technology has been allowed and even invested in by major companies and endorsed by governments at the local level.

Absent the ability to remove those stories, authorities have since issued new rules that will require people to verify their identities when signing up for blockchain services, a move that will likely stop future would-be activists from preserving any more censored news. Typically anonymous blockchain users will now have to reveal themselves, similar to how other social media platforms in China work.

As Shazeda Ahmed, a PhD student at UC Berkeley who studies cybersecurity and internet policy in China, puts it, “The push for real-name registration grows stronger by the year. It’s difficult to sign up for any app or service without tying your account to some form of official ID, or a phone number that itself is linked to one’s state ID.” Meanwhile, banking and payment apps are starting to request biometric data including fingerprints, voice recordings, or facial recognition.

Many experts on China agree that the internet appears to be slipping under a more authoritarian rule, after a brief open window where it appeared that China’s growing economic freedom might lead it in a different direction.

“Generally speaking, the internet regulator is growing more authoritarian,” says Séverine Arsène, an associate researcher at the French Centre for Research on Contemporary China. She points out that the internet regulator has gained more substantial powers under a new name that will be more directly led by the Chinese Communist Party. “In terms of the policies, it is hard to measure, but there have been a few interesting events.”

Arsène cites the closure of Bytedance’s Neihan Duanzi — a popular parody and meme app that was shuttered back in April for containing vulgar content on the platform that, the Cyberspace Administration claimed, “triggered strong resentment from internet users” — as having been “a pretty bold move, and one mostly directed at popular subcultures.” (In the wake of its removal, Neihan Duanzi fans began to seek each other out offline by randomly honking on the streets, only to face fines for inappropriate honking.)

“This year has been an escalated cat-and-mouse game with periods of tighter control. People have just been finding any means of posting about these stories,” says Christina Xu, an ethnographer who studies tech adoption and internet culture in the US and China. “Chinese internet users are incredibly savvy. It’s tough to algorithmically flag their comments — they could be a subtweet of a subtweet, a thinly veiled historical reference, a euphemism with no keywords. But regulators are just as savvy, and they’ve caught on ... There are fewer of those little nooks and crannies that you could once go to where people weren’t really paying attention.”

Besides offline communication and the blockchain, internet users also have virtual private networks, or VPNs, as a recourse. But in March, the internet regulator drafted new rules that would ban non-state sanctioned VPNs from being used. Although the ban hasn’t been implemented yet, leaving many popular VPNs still functioning in China, including ExpressVPN and NordVPN, a shadow looms over this last viable way to escape internet censorship.

There are several canaries in the coal mine — take the case of famous actress Fan Bingbing, for instance. The common practice of tax evasion by China’s top celebrities has become a crime worth months of detainment and costly fines. Her reappearance after several months coincided with the disappearance of Interpol chief Meng Hongwei, who remains missing, signifying China no longer cares about how it comes across to the rest of the world. Meng’s wife told the BBC in October that she feared he was dead, given that he had sent a knife emoji to her right before vanishing and that she had received threatening phone calls since then. “There’s something fundamentally different this year,” says Xu. “There are strong signals being sent that we’re in a newer, stricter time.”

Overall, the two posts that remain live — one an example of journalism that can still exist in China even as freedom of speech gets restricted for most media and another proof that the #MeToo movement in China can’t be stifled — can be considered huge wins for Chinese internet users starting to express discontent with societal ills in 2018. As Xi gets into his sixth year of presidency and China’s internet regulator grows more centralized, acts like these feel more elusive and fleeting. But whether it’s through the blockchain, or through a subtle emoji, Chinese users have proven repeatedly that they have many means of sending a message across. Next time, it may be through an entirely unexpected form.