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.
ESP32 WiFi Bootstrap is a lightweight, high-performance Wi-Fi provisioning solution for the ESP32. It provides a user-friendly captive portal experience with fast configuration, persistent storage, and full compatibility with ESP-IDF 5.4 or later.