BoAT MER Guide

Build profiles and porting

Compile only what the device needs. A buyer does not carry the seller's code, and the seller profile fits an ESP32-C3.

Add it to an ESP-IDF project#

BoAT MER is an ESP-IDF component. Reference it by git tag — it is not on the component registry.

bash

cd your-esp-idf-project
mkdir -p components
git clone https://github.com/TLAY-IO/boat-mer.git components/boat-mer

Choose a profile#

bash

idf.py -DBOAT_PROFILE=full build     # everything
idf.py -DBOAT_PROFILE=buyer build    # buy only
idf.py -DBOAT_PROFILE=seller build   # sell only, fits ESP32-C3

Module	full	buyer	seller
Crypto (secp256k1 + Keccak)	✓	✓	✓
Ed25519	✓	✓	—
Nanopayment	✓	✓	✓
Attestation	✓	✓	—
x402 pay	✓	✓	—
x402 offer	✓	—	✓
Lightning	✓	✓	—
HashKey Multi-Pay (host builds only)	✓	✓	—

Careful

Use idf.py -B build-variant … for each profile or target. A stale CMake cache will silently produce a binary configured for a different target than you asked for.

What has run where#

Target	Platform layer	Status
ESP32-C3	`pal/esp-idf/`	verified on hardware — buyer and seller profiles
ESP32-S3	`pal/esp-idf/`	verified on hardware
Linux / macOS	`pal/linux/`	verified — host builds and the full test suite
Other MCU families	implement `boat_pal.h`	portable, not verified by us

It is developed and built against ESP-IDF 5.5.x; older lines are untested rather than known-broken. Host builds link OpenSSL and curl; the ESP-IDF build links neither.

Port to another microcontroller#

Implement boat_pal.h. The core set is small:

storage read and write — where the keys persist
random — for key generation and nonces
time
SHA-256
HTTP POST
logging

The extra entry points (boat_pal_http_post_ext, boat_pal_http_get, boat_pal_http_post_hashkey) are only needed by the modules that use them, so a minimal port does not implement everything. Use pal/esp-idf/ and pal/linux/ as references.

Tip

Secure elements and hardware-backed storage strengthen the guarantee that the key cannot be taken. Wire them in through the storage and crypto entry points of your port.