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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 tree

The planned layout of all the topics a system uses.

A topic tree is the designed hierarchy of topics -- typically site/device/kind/name with separate telemetry, command and state branches -- chosen so subscribers can select exactly what they need with wildcards.

Examples

  • The greenhouse uses <site>/<device-id>/<kind>/<name>, like gh1/dev-a1/telemetry/temperature and gh1/dev-a1/cmd/fan.

  • With that tree, gh1/+/telemetry/# gets every reading on the site in one subscription.

See also

topic topic filter telemetry command
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