X Corp has sent cease-and-desist letters to Nitter, the open-source project that let people read X posts without an account. Nitter.net is offline and development has stopped. Its creator says he is seeking legal advice. XCancel, the best-known site built on Nitter, has also stopped operating.

Sarah Perez has read one of the letters and reported it for TechCrunch. X gave Nitter until 5pm Eastern on 25 August to shut down.

What the letters demand

The message now on Nitter’s site says the letters arrived on 24 August. They demand a permanent takedown of Nitter instances and of the project’s repository. The developer, who goes by the handle Zedeus, wrote that he will not comment on the specifics for now. He thanked everyone who used, hosted, packaged, donated and contributed to Nitter over the past seven years.

He told TechCrunch by email that other Nitter instances had received similar letters. A version of the same notice sits on the project’s GitHub page, where the code has lived since 2019.