Lattice
Lattice Node + Pebble: relay capacity for the mesh.
A spare phone or a £15 dev board you flash in five minutes becomes a relay for every Lattice user near it. Coverage grows the same way Meshtastic's did — volunteers, deploying hardware where they live and where they pass through.
Status: Direction captured in RFC-0021. Lattice Node app ships in M16; Lattice Pebble firmware ships alongside post-v1.0.
Two products. Same job.
Lattice Node — the relay-only app
Tiny Android (later iOS) app whose entire user-facing surface is "I'm relaying. Tap to see status." No chat tabs, no contacts, no identity. People install it on a spare phone they leave plugged in at home. The phone becomes a relay for every Lattice user within Bluetooth / Wi-Fi range — including the messenger users in their own household.
- APK target: under 2 MB stripped.
- Battery: ~4-8% per day on a phone left plugged in (foreground service ceiling).
- Identity: ephemeral relay-key generated at first launch. No Bullet ID, no contact list, no message storage.
- Optional add-ons: LoRa USB-C / BLE-tethered, Wi-Fi Aware, Meshtastic interop, ultrasonic. All toggleable in the status panel.
Lattice Pebble — the dedicated hardware
An open-source firmware you flash onto a low-cost dev board to turn it into a permanent Lattice relay. Hockey-puck-shaped (or whatever case you screw it into), USB-C charged or solar-powered, IP65 if you want to put it outside.
We don't manufacture. We don't sell hardware. We publish the firmware as a precompiled binary and the reference PCB designs as open hardware — anyone can fabricate, anyone can flash, anyone can sell.
The free firmware download.
The whole point of Lattice Pebble is that it's free to deploy. You don't pay us, you don't register the device, you don't tell anyone what you're doing. Buy bare boards from AliExpress (or pull a spare ESP32 out of a drawer), download the firmware here, flash it, plug it in, walk away.
What we publish at lattice.fyi/pebble/firmware
- Precompiled
.bin/.uf2for every supported board, signed and reproducibly built. - Source code under MPL 2.0 (published with v1.0 of the messenger).
- Reference PCB design files under CC-BY-SA — Gerbers, BOM, schematic.
- Step-by-step flash instructions per board, no special tooling beyond what the board's vendor already requires (
esptool.py,picotool, drag-and-drop UF2, etc.).
Compatible boards (target list).
| Board | Chip | Cost (bare) | Radios | Power |
|---|---|---|---|---|
| ESP32-S3-DevKitC-1 | ESP32-S3 | ~£3 | BLE 5 + Wi-Fi | USB-C |
| Heltec WiFi LoRa 32 (V3) | ESP32-S3 + SX1262 | ~£20 | BLE + Wi-Fi + LoRa | USB-C, optional 18650 |
| LILYGO T-Beam Supreme | ESP32-S3 + SX1262 + GPS | ~£40 | BLE + Wi-Fi + LoRa | USB-C, 18650 case included |
| RAK Wireless RAK4631 | nRF52840 + SX1262 | ~£30 | BLE + LoRa | USB-C, optional battery |
| Raspberry Pi Zero 2 W | ARM Cortex-A53 | ~£15 | BLE + Wi-Fi (+ LoRa HAT) | USB-C |
| Raspberry Pi Pico W | RP2040 | ~£6 | BLE + Wi-Fi | USB-C |
Honesty note. Until M16 ships the firmware, none of these are tested end-to-end with Lattice. If you're shopping ahead, focus on chipset + radio rather than brand. Anything based on ESP32-S3, RP2040, or nRF52840 with a BLE radio is plausibly compatible.
Solar deployment.
Outdoor Pebble setup, ~£35 in parts:
- ESP32-S3 + LoRa SX1262 board (Heltec V3 or equivalent) — ~£20
- 2 W solar panel — ~£8
- 1000 mAh LiFePO4 cell — ~£5
- TP4056 charging module — ~£1
- 3D-printed IP65 case — pennies
The Lattice firmware is power-aware: if battery drops below a threshold, it puts the radio into low-duty-cycle mode (1 packet per 30 s instead of constant) until charge recovers. A cloudy week shouldn't bring the device down.
Reference deployments planned for documentation: a windowsill in a city flat, a fence-post in a rural garden, a cafe wall-socket. The hope is volunteers fork the docs and publish their own deployment guides for new locations.
Why we don't manufacture.
Three reasons.
- Resilience. A network whose relay capacity depends on a single supply chain is fragile. If we shipped "the official Lattice Pebble" and stopped making them in five years (which would happen — small hardware companies have notoriously short lifecycles), the network's relay capacity collapses with us. With open hardware, the network outlives us.
- Cost. A small batch of artisan Lattice-branded devices would cost £80 each. The same hardware off AliExpress is £15 in parts. The price-to-deployment-density ratio matters more than aesthetics.
- Values. Lattice exists because we don't trust centralised infrastructure. Becoming centralised infrastructure for the relay layer would be incoherent.
Where vendors want to produce pre-flashed, cased Lattice Pebbles for non-technical buyers — fine. We'll list them on this page. There can be many such vendors; we are none of them.
For the curious.
- RFC-0021 — full technical design including the Lattice Node Android app and the Pebble firmware.
- LoRa, Meshtastic interop, and the wider piggyback strategy — how Pebbles plug into the broader transport story.
- Meshtastic — the LoRa-mesh project that proved volunteer-deployed hardware mesh works at scale.