In the readme they say they use the unofficial API: "Uses Twitter's unofficial API (no rate limits or developer account required)".<p>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.<p><a href="https://github.com/zedeus/nitter/blob/d7ca353a55ea3440a2ec1f09155951210a374cc7/src/consts.nim">https://github.com/zedeus/nitter/blob/d7ca353a55ea3440a2ec1f...</a><p><a href="https://github.com/zedeus/nitter/blob/d7ca353a55ea3440a2ec1f09155951210a374cc7/src/tokens.nim">https://github.com/zedeus/nitter/blob/d7ca353a55ea3440a2ec1f...</a>