Hey everyone,

First of all I want to admit that this project is a product of spite, but I won't go into the details. Anyway, here's what I've been building over the past month.

It's called Heimdall an ESP32 firmware that sits quietly on your home network and wakes (or sleeps) any PC remotely over MQTT. No port forwarding, no dynamic IP problems.

How it works in practice:

Plug an ESP32 into a USB charger anywhere on your home network. First boot creates a WiFi AP connect from your phone, fill in your WiFi and MQTT broker details, and you're done. After that it runs silently, waiting for a MAC address payload on its MQTT topic. When it gets one it broadcasts the magic packet. That's it.

One relay can wake any PC on the network the target MAC travels with the command so nothing is hardcoded on the device.

Three build profiles:

* STANDARD plain topics, ping feedback to confirm the PC actually came online, GPIO control, status LED
* HARDENED adds TOTP auth on every command, HMAC-derived opaque topics, MAC spoofing, hostname obfuscation
* HARDENED STEALTH strips LED, ping, GPIO, and response channel entirely. Silent footprint

There's also a companion script that runs on the target PC and puts it to sleep on command, so you get a full remote power cycle both ways.

No toolchain needed there's a web flasher at the GitHub Pages link. Plug in your ESP32, open Chrome, pick a profile, click flash. Takes about 90 seconds.

What I'm trying to figure out:

* Does the captive portal auto-detect on your phone? The moment you connect to the setup AP and type anything into your browser's address bar, it should automatically redirect you to the portal IP (e.g. you type "h" and it takes you straight to http://x.x.x.x) no need to type the full address manually.
* Does it connect cleanly to your MQTT broker? Tested mainly on HiveMQ Cloud curious about Adafruit IO, self-hosted Mosquitto, or anything else
* Does the ping feedback actually confirm the PC woke up, or does it ping too early before the NIC is ready?
* Any issues with the web flasher on Edge or Opera?
* Are there any other bugs that I didn't see ?

Repo: \[https\] ://github.com/SS-Sauron/Heimdall-Wake-On-Lan-ESP32

Web flasher: \[https\] ://ss-sauron.github.io/Heimdall-Wake-On-Lan-ESP32/

Written in C on ESP-IDF v6.0.1. Issues and PRs welcome there's a roadmap in the docs if you want to see what's coming or contribute.

Looking for testers ! I built a Wake-on-LAN relay for a ESP32. flash it from your browser, no IDE needed.