the bill · part four

The Backbone

The hub, the radio, the network, and the energy layer — the part nobody sees and everything depends on.

The Hub

home assistant on kara · shared box, good fences

The deployment

Home Assistant Container + Mosquitto + Zigbee2MQTT in their own Docker compose project on kara, with an SMLIGHT SLZB-06M PoE Zigbee coordinator (~$45) — network-attached, so there's no USB passthrough and the radio mounts wherever coverage is best. Ports claimed: 8123 (HA), 1883/9001 (MQTT), 8080 (Z2M) — all free on the box's current map.

  • Good-neighbor rules on the shared hub: own Postgres database and role, resource limits on every container, HA alone on host networking (Sonos and ESPHome discovery need it).
  • Z2M over ZHA because it runs as its own process — a busy hub can't stall the Zigbee mesh.
  • Coordinator value tier: the Sonoff ZBDongle-E (~$20) — same chip family, but USB, which drags the passthrough problem back onto the shared box. Worth it only as a spare; the PoE unit is the pick for a reason.
  • kara housekeeping: a DHCP reservation (its IP wandered after the July outages), and Ethernet instead of WiFi when the attic run happens — an alert-critical box shouldn't ride wireless forever.
  • Thread/Matter: not yet — watch it for smoke/CO alarms specifically, skip it elsewhere.

The Network

all fiber, no copper · wired APs, not mesh

The plan (~$520, keyed to the AT&T date)

BGW320 in IP Passthrough with its radios off (no true bridge mode exists; passthrough hands the router the public IP) → UniFi Cloud Gateway Ultra ($129) + U7 Pro indoor ($189) + U7 Outdoor ($199) under the eave facing the deck. Real VLANs — a client-isolated IoT network for the 30-plus gadgets — with AdGuard Home on the hub as DNS for all of them. The outdoor AP is the actual recteq fix.

  • On mesh, once and finally: wireless backhaul still halves throughput per hop — better radios, same physics. Wired-backhaul APs aren't mesh; they're switch ports with antennas. That's what this is.
  • Zero-drama cutover: run AT&T and Xfinity in parallel, stand up the new SSIDs, test the IoT VLAN with a few devices, batch-migrate the fleet (the slow part), cancel Xfinity after 48–72 stable hours. Then sell the Decos ($60–120 as a kit) or keep one as a wired spare.
  • Gotchas that recur: BGW320 firmware pushes can re-enable its WiFi and occasionally reset passthrough — recheck after updates. Size the IoT DHCP pool generously.
  • Value tier: TP-Link Omada runs the same wired-AP architecture for less — ER605 gateway + EAP670 indoor + EAP650-Outdoor lands around $370. UniFi buys a nicer controller and ecosystem; both beat any mesh.

Energy & the Fun Radio

measure the house · hear the neighborhood

  • Emporia Vue 3 (~$170) on the panel — whole-house plus per-circuit, including the future mini-split run. One decision before install: stock cloud polling, or the community ESPHome reflash for full local (voids warranty). Given the local-first rule, the reflash is on-brand; decide with eyes open.
  • ThirdReality Zigbee plugs (~$12–15) where device-level truth matters — they meter, they repeat the mesh, and one of them is already assigned: the radon fan's health monitor (Resilience).
  • RTL-SDR Blog V4 (~$35) — one dongle, two hobbies: ADS-B flight tracking with the antenna already owned, and rtl_433 passively hearing every cheap 433MHz sensor and half the neighborhood's weather stations. The plane-overhead announcer (SDR → Ollama → Sonos) remains the wilder shelf's crown jewel — still unbuilt by anyone, per the June research.
  • The mystery ESP32 (10.0.0.196): browse to it, check its MAC's device page, or serial in — cheapest identification first, reflashing decisions later.

Voice

"hey house" · mics in rooms · brains on the hub

What a home assistant looks like here, concretely: a small satellite mic per room listening for a wake word on-device (nothing streams until it hears it), piping speech to kara, where the whole pipeline runs local — Whisper for speech-to-text, a brain, Piper for the voice coming back.

The hardware

Home Assistant Voice Preview Edition (~$69/room) — the turnkey satellite, built by the HA people for exactly this. Start with one in the kitchen; add rooms if the family actually talks to it. (The old Echos stay demoted to dumb announcers — they're cloud-locked and always will be.)

  • The brain is a dial, not a religion: HA's Assist handles device intents natively with no LLM at all ("lights off," "set the office to 72" — instant). Behind that, Ollama on kara (free, private, a few seconds on CPU with a small model) handles casual asks — and for the genuinely conversational layer, HA's Anthropic integration can route the hard questions to Claude. Local for commands, cloud only where it's worth it.
  • The four asks, specifically: "check the weather" — answered from the Tempest's own readings, not a forecast site. "add milk to the grocery list" — HA's todo list, which the kitchen printer can tear off on demand. "log a diaper" — the flow Noctling's design notes already specify: speech → structured event → validated write into the app, tagged as voice-sourced. "play a song" — Music Assistant targets the Sonos by room name.
  • Order of operations: this rides on the backbone — HA + the hub first, one satellite second, the diaper-logging bridge last (it touches Noctling, so it gets built with the same care as the app).