Krux Review
Open-source signing device for multiple hardware platforms
Krux takes the SeedSigner concept and runs with it. Instead of one hardware platform, Krux supports multiple devices including the M5StickV and Maix Amigo. Same stateless security model. Same DIY ethos. More hardware options means you can pick what works for your budget and availability. It's SeedSigner with flexibility.
Krux exists because Bitcoiners wanted more hardware options for DIY signing. The community built and maintains it with zero corporate influence. Bitcoin-only from conception. Every feature exists to make self-custody more accessible.
About Community Project
Security Architecture
Stateless DIY signing device. Similar concept to SeedSigner but supports more hardware.
| Secure Element | None (software security) |
| Connection Methods | QR codes only (air-gapped) |
| Display | Varies by device |
| Passphrase Support | Yes |
| Multisig Support | Yes |
The Strengths
Hardware Flexibility
Runs on multiple devices including M5StickV and Maix Amigo. Choose your preferred hardware.
Stateless Security
Like SeedSigner, keys are never stored. Generated fresh each session.
Extremely Affordable
Can be built for as little as $30-40 depending on hardware choice.
Where It Falls Short
DIY Required
Must source hardware and flash firmware yourself.
No Secure Element
Software-only security. Physical attacks possible.
Less Mature
Newer project than SeedSigner with smaller community.
Trust Assessment
Reasons to Trust
- Fully open-source
- Stateless design
- Multiple hardware options
- Air-gapped via QR
- Bitcoin-only
- Community-driven
- Very affordable
Concerns
- DIY assembly required
- No secure element
- No commercial support
- Requires technical knowledge
Best For
- Technical users who want hardware choice
- SeedSigner alternatives
- Budget-conscious DIYers
- Those who want specific form factors
Specs Overview
$40
8.8/10
Bitcoin-Only
DIY, Open Source, Stateless
Varies by device
QR codes only (air-gapped)
Frequently Asked Questions
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The Verdict
Krux is excellent if you want DIY flexibility. The hardware options mean you can actually find parts when Raspberry Pis are scarce. The stateless design is sound. At $40 or less in parts, the price is right. It's slightly less polished than SeedSigner but the multiple device support is a real advantage. For technical users who want choice, Krux delivers.
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How Krux Compares
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