ESP32 Rust

Std Rust on an Inland ESP-WROOM-32 dev board with end-to-end OTA over GHCR + cosign keyless signing. Optional Cloud Logging + Cloud Monitoring shipped from the device. E-ink display work coming next.

What it does today

• Polls ghcr.io/imjasonh/esp32:latest every ~60 s for new firmware.
• For each new digest: fetches the cosign Sigstore Bundle, verifies the signature + cert chain to the Sigstore root + that the signer's identity matches the allowlist provisioned into the device's NVS.
• On verify-pass, streams the layer to the inactive OTA partition, reboots, marks the new image valid only after Wi-Fi + registry bringup checks pass. Any post-OTA failure auto-rolls back via the bootloader.
• Optionally ships structured tracing events to Cloud Logging and chip-health metrics (heap, stack, wifi, cpu, …) to Cloud Monitoring. Opt-in per device via the [gcp] block in provisioning.toml.

Push to main → CI builds → publish workflow pushes a signed image to GHCR → device picks it up on its next poll.

Docs

• docs/setup.md — prerequisites, first flash, day-to-day commands, GCP setup
• docs/ota.md — OTA + provisioning + signing design
• docs/observability.md — Cloud Logging + Cloud Monitoring design (current state)
• docs/eink-plan.md — planned e-ink display work

Quick start

cargo install espup espflash ldproxy
brew install cmake ninja dfu-util cosign jq
espup install --targets esp32
curl -LsSf https://astral.sh/uv/install.sh | sh

make provisioning.toml             # creates from template
$EDITOR provisioning.toml          # fill in wifi creds + trust identities
make bootstrap                     # build, flash everything, write NVS
make monitor                       # watch it boot and connect

See docs/setup.md for full details, including optional GCP Logging + Monitoring setup.