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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

rollback

Going back to the previous working firmware when a new one fails.

Rollback reverts the boot selection to the last image marked valid, triggered automatically after a failed trial boot or explicitly by the application.

Examples

  • A new image that fails its self-test calls esp_ota_mark_app_invalid_rollback_and_reboot(), and the fan controller restarts into 1.4.0 from the other slot.

  • A watchdog reset during a hung trial boot also ends in a rollback, because the image is still pending.

See also

trial boot health gate A/B update
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