SeedHammer

After more than a year of iterative design and testing, our electronics have progressed through multiple PCB revisions - evolving from the Raspberry Pi Pico 1 to a fully custom design built around the RP2350 chip, designed with KiCad and manufactured by JLCPCB.

Shipping status: - We are assembling additional machines for the upcoming shipment batch. - We are investigating defective hammerheads supplied by the factory. - We’re also working on CE certification to get through EU customs.

We are finally shipping! Everyone that ordered on or before December 22 should have received an email with instructions. We are shipping from Switzerland and have postponed US shipping until the tariffs issue settle.

We're raising the price of the SeedHammer II machine soon. If you're still on the fence, act now to get a machine at the pre-order price. We had hoped to keep the current price after the pre-order phase, but it's now clear to us that we need to work on raising sales volume first.

We're big fans of codex32 at SeedHammer. Hand-computable, built in Shamir's secret splitting and fixes several shortcomings in BIP39 (Ctrl-F "trainwreck" in

Codex32: An Illustrated Secret Sharing Guide

). The SeedHammer machine may be the first hardware to support codex32. Below is the engraving of 2 codex32 Shamir shares that combine to a master secret. We also wrote a command line utility and library for manipulating codex32 shares and derive BIP85 data. See

Go Playground - The Go Programming Language

(press "Run" to see output) or use a terminal (you need Go installed): Install the `biptool` command line tool: $ go install seedhammer.com/cmd/biptool@latest $ export PATH=$PATH:~/go/bin Encode a secret with threshold 2. Usually a random key, but in our case a sentence: $ echo "Codex32 is what we do"| biptool seed -seedlen 22 -id secr -threshold 2 ms12secrsgdhkgetcxvezq6tnypmksct5ypmk2grydu9qqd7chr26ruhsn Encode share #1: $ head -c 22 /dev/urandom | biptool seed -seedlen 22 -id secr -threshold 2 -idx a ms12secras2eph54xt3tkzjhrnp8g8k2zpaq5rrgqzu2sfvvug3l4xxqqc Derive share #2: $ biptool interpolate -idx c # Enter the secret share and share #1, finish with Ctrl-D ms12secrsgdhkgetcxvezq6tnypmksct5ypmk2grydu9qqd7chr26ruhsn ms12secras2eph54xt3tkzjhrnp8g8k2zpaq5rrgqzu2sfvvug3l4xxqqc <Ctrl-D> ms12secrca5vwy33zw9af9w5jupyvgra6c7ang0ywqugpzm6jm8hhlv035 Now you have two Shamir shares for your secret. Combine them to extract the secret: $ biptool derive seed # Enter share #1 and #2, finish with Ctrl-D ms12secras2eph54xt3tkzjhrnp8g8k2zpaq5rrgqzu2sfvvug3l4xxqqc ms12secrca5vwy33zw9af9w5jupyvgra6c7ang0ywqugpzm6jm8hhlv035 <Ctrl-D> Codex32 is what we do Don't have a terminal? Play along in the browser:

Go Playground - The Go Programming Language

. Edit the program, press "Run" and see output below the code box. #SatHunterz

Meet our engineer @Snick and come and see the Seedhammer II today at #BH2025 ! He is in the book corner with @Knut Svanholm ∞/21M, @Luke de Wolf and @Daniel Prince ‘s books.

Here’s our first test engraving of a complete 2-of-3 multisig descriptor. Still a bit off-center, but progress is progress. We're overhauling descriptor support in the SeedHammer II firmware: - Seeds and descriptors can be engraved independently. - Descriptors are engraved in clear text and are no longer split among several plates. - Descriptors are engraved either text+QR (only singlesig), text only or QR only (your choice).

Announcing SeedHammer II Compact, light and operated by builtin touchscreen, this is the machine we wanted when starting SeedHammer. Preorder here: -

Geyser | Bitcoin Crowdfunding Platform

A Bitcoin crowdfunding platform where creators raise funds for causes, sell products, manage campaigns, and engage with their community.

(lightning) - https://seedhammer.com/shop (on-chain) SeedHammer II is smaller than a 21cm cube and less than 4kg so you can fit it in a backpack. The large LCD and touchscreen eliminate the need for an external controller. The control board and LCD are designed to be replaced, so you can safely share a SeedHammer II. A replacement kit is $89, comparable to the cost of a manual engraving kit. The SeedHammer II OG limited edition is for you with the means to support the project. In return we will ship to you 1 of the 21 high-quality machines, and print your name or alias on every control board produced during the fundraiser.