ESP-IDF captive portal component with Wi-Fi configuration, scanning, DNS hijacking, mDNS, and HTTP server. Directly usable as an API component for any ESP32 series.
This is an ACME client for ESP (ESP32, etc) devices, so your IoT can fetch their own certificate for secure communication. ACME is a protocol (see RFC8555) for automatic certificate management. Sites such as letsencrypt.org allow you to obtain free (no charge) certificates in an automated way using the ACME protocol.