How is Nitter still working?

Twitter hasn't fully removed their APIs just yet.

Scraping?

In the readme they say they use the unofficial API: "Uses Twitter's unofficial API (no rate limits or developer account required)".

Browsing quickly the source code, it looks like they maintain a pool of short lived guest tokens using magic constants probably grabbed while doing reverse engineering. Some code looks very much to be about the rate limits too.

https://github.com/zedeus/nitter/blob/d7ca353a55ea3440a2ec1f...

https://github.com/zedeus/nitter/blob/d7ca353a55ea3440a2ec1f...

Nice try, Elon.