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Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

topic

The slash-separated name a message is published to, like home/kitchen/temp.

A topic is a UTF-8 string of levels separated by /, named by each publish; it is not created in advance and contains no wildcards.

Examples

  • The bench 1 temperature is published to gh/bench1/temp, a topic with three levels.

  • gh/bench1/temp and GH/bench1/temp are two unrelated topics, because matching is case-sensitive.

See also

topic filter topic tree publish/subscribe
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