M5Stack Power Sentinel

Power Sentinel is a local homelab companion for the M5Stack CoreS3 + Module LLM stack. It surfaces homelab state on an Ambient Console without becoming a replacement control plane for NUT, Proxmox, Home Assistant, or other specialist tools.

The public v1 release target is a First Public Release User: a technically capable homelab owner who can assemble the supported M5Stack hardware stack, use Linux/SSH on the Module LLM, edit /etc/power-sentinel.json, configure read-only integrations, and flash the CoreS3 through USB/PlatformIO.

Screenshots

Fresh LVGL MCP fixture renders of the two public v1 Module Pages:

NUT Monitor	Proxmox Module

The MCP renders are visual/layout evidence, not a claim of pixel-perfect CoreS3 panel emulation. See the module docs for multi-state contact sheets.

What is supported in public v1

• NUT Monitor: supported default module. Power Sentinel observes UPS/NUT state and displays power readiness. NUT and upsmon own real shutdown behavior.
• Proxmox Module: supported optional module. It is API-only, read-only, disabled by default, and aimed at a single-node homelab Proxmox installation.
• Backend Installer: installs and updates the Module LLM/Linux services, systemd units, module config template, backend health checks, and the read-only powersentinel operator CLI.
• Firmware Release Path: USB/PlatformIO build and flashing for the CoreS3 live firmware.
• Configuration Surface: /etc/power-sentinel.json plus read-only validation/troubleshooting commands such as powersentinel doctor.
• Public Repo Audit: release-blocking audit for secrets, private lab assumptions, unsafe examples, license/security guidance, and generated artifacts.

Known public v1 limitations

• English-only public documentation.
• no OTA firmware updates in v1.
• no Module LLM-mediated flashing in v1.
• no CoreS3 setup/options page in v1.
• no mutable config CLI or web UI in v1.
• no Wi-Fi/HTTP polling fallback in the CoreS3 firmware; live data uses StackFlow/UART.
• no Proxmox SSH, remote shell commands, guest controls, backup management, storage/network changes, or console replacement.
• NUT and upsmon own real shutdown behavior; Power Sentinel only observes and displays the shutdown-relevant condition.

Public documentation

Start here:

• Quickstart
• Hardware and transport assumptions
• Backend Installer
• Configuration Surface
• CoreS3 Firmware Release Path
• NUT Monitor
• Proxmox Module
• Troubleshooting and Public Repo Audit
• Public Repo Audit checklist
• Security policy
• License
• Third-party notices

Maintainer/dev-unit evidence lives under docs/operations/. Those files can explain why hardware or architecture decisions were made, but they are not the public install path.

Repository layout

backend/
  bin/                              operator CLI, local API, StackFlow unit, NUT diagnostics
  config/                           sanitized configuration examples only
  systemd/                          service unit files
  tests/                            stdlib-only regression tests
firmware/core-s3-display/           CoreS3 PlatformIO firmware
scripts/install-power-sentinel.sh   Backend Installer for Module LLM/Linux
docs/                               public docs, architecture notes, ADRs, operations evidence
tools/                              test, guard, and serial-capture helpers

Verification gates

The main release-readiness gates are:

python3 tools/run_tests.py
python3 tools/check_core_s3_ui.py
python3 tools/check_public_release_docs.py
scripts/install-power-sentinel.sh --modules nut --dry-run
scripts/install-power-sentinel.sh --modules nut,proxmox --dry-run
powersentinel doctor
cd firmware/core-s3-display
pio run -e m5stack-cores3

Use the quickstart and module docs for the full install and verification flow.