Keycard Shell

Card-based wallets are having their moment… but the real differentiator isn’t the card, it’s the philosophy behind it. Keycard Shell is built for verifiability: • Open-source hardware + firmware • Air-gapped signing via QR • Modular setup (swap cards, scale backups anytime) • Works across multiple wallets, no lock-in • Every action verified on-device It’s a system designed for people who prefer independence over assumption. Different wallets optimize for different things. Keycard optimizes for control, transparency, and flexibility 🔑

QR hardware wallets introduce interesting UX flows where you don't need to physically connect the device to your computer. Using Keycard with @ambire means less complexity for hardware wallet users. You maintain control while enjoying simpler wallet UX.

my next plan is to: - wait for kohaku release - get a @Keycard_ - move my assets there

@ambire @borislavItskovv it's open source, open a PR 😉

@borislavItskovv @Keycard_ Can you play 8-bit games on it?

POV: You can now connect QR hardware wallets to Ambire What is the best QR hardware wallet out there? Asking for a friend

We believe users should own their keys in the most modular, open-source & resistant manner, and we think smart cards are a good answer ... Users then decide how to use those keys: mobile (they decide which wallet they trust), desktop (same), or Shell for an air-gapped hardware wallet with a trusted display. To our knowledge, this is the only architecture where users can reasonably easily build their own secure element since Java Cards are a commodity, and they're programmable.👇 docs.keycard.tech/en/developers/…

@liftlines No on-device transaction decoding though.

What a real hardware wallet should look like folks 👇🏼 Replaceable battery. Separation of Keys - Signing Device - Wallet App (Stop blind signing) Air-gapped QR code based signing. Swappable keycards (as many keys and backups as you like). No firmware upgrade can touch your keys.

Don't buy dog shit @Ledger always buy @Keycard_ 🐇

I got this awesome @Keycard_ and I can't wait to set it up. It looks amazing even before I've started using it

@trxdfos @liftlines happy to discuss, what would you like to see?

@liftlines @Keycard_ Using keycard you cannot verify the entropy of your wallet. Very, very bad move

If you can’t replace the battery in your hardware wallet, or separate and secure the keys so that no firmware upgrade can touch it, then is it really worthy of your trust? Don’t fall for slick marketing Only @Keycard_ ticks all the right boxes for ETH and BTC hardware-wallets.net/keycard-shell-…

@SpadesHQ @Thealphacruze @Ledger We claim to be the most open source hardware wallet We are happy to be challenged and discuss the claim ofc Here's our comparison #gid=0" target="_blank" rel="nofollow noopener">docs.google.com/spreadsheets/d…

@Thealphacruze @Ledger @Keycard_ First time hearing about Keycard. Is it open source? I ditched ledger awhile ago and have been using paper wallets.

hardware wallets should have standard replaceable batteries 👉 keycard.tech

Using @Ambire? You can now use Keycard to sign your transactions. Air-gapped. Verifiable. No firmware surprises. Ready to level up your setup?

@0xSuperKalo @ambire @keycard_ shell works with Ambire ✅ and even more importantly we fully agree that QR codes (ERC-4527) is the only open and interoperable signer (hww)-to-wallet interface, and it's great to see being adopted that much

Support for QR-based (air-gapped) hardware wallets just landed in @ambire with the v6.4 series 🎉 I’m genuinely excited about this one! Until now, hardware wallet support meant tight coupling to vendor SDKs (Ledger, Trezor, GridPlus). That works, but it doesn’t scale well and slows everything down to the pace of each vendor. QR-based changes the game. One protocol support means onboarding multiple devices. We tested & added how-to-s with @KeystoneWallet and @imTokenOfficial, but all that use the same communication like @ngrave_official, @AirGap_it, @OneKeyHQ (and more) should on work 🔌 If you’re building a QR-based hardware wallet, please reach out. Happy to dry-run integrations, test flows, and help prepare guides so users can plug in seamlessly ⚡️ By supporting it, we unlock a whole category of hardware wallets without needing custom integrations per vendor. That's effectively the only broadly adopted protocol that new hardware wallet projects can integrate with for mainstream adoption. This also opens the door for cypherpunk / DYI setups (e.g. Specter DYI air-gapped hardware wallet). Would love to see more devices and users onboard this path ☀️

This is cool! I can use my @Keycard_ with @ambire now. Pretty good setup for hardware level security.

Honestly, with each passing day, I understand less and less why I did not buy it earlier. It is incredibly convenient to use. In my opinion, from a user experience perspective, this is one of the best solutions I have tried. Everything is made to feel as simple and seamless as possible. For comparison, even on Keystone the camera often takes a while to scan a QR code, while here it works almost perfectly.

@patron4eg So great to read this, thank you! Indeed we crafter every detail of the UX to make it as fluid as possible especially when you're juggling with multiple keys and wallets 🙏

I started heavily using my @Keycard_ Shell with @Rabby_io. The UX is just perfect, swapping cards in an instant. I might order another Shell, this is too useful to only have one. (My fiancée thinks I'm some kind of spy, seeing me scanning & showing QR codes all around my screens & webcam)

Tangem "no more seed" approach sounds nice of course but few understand the consequences of this seedless approach. First, you can't add new cards after setup 🥴 Second: - if you leave 'recovery mode' enabled, then anyone who gets hold of two of your cards can reset your PIN and can access all your funds 💀 - if you disable 'recovery mode', then forgetting your PIN locks you out permanently 💀

A Hardware Wallet with a Soul In the hardware wallet space, we've long accepted compromises that quietly erode our sovereignty. Most devices remain monolithic — one sealed unit handling key storage, signing, screen display, and logic all at once. They're often partially closed-source, tied to vendor apps with custom APIs, burdened by batteries that fail over time, and vulnerable to firmware updates that can silently alter behavior. Keys end up bound to a single piece of hardware, leaving our autonomy conditional on the manufacturer's goodwill. The Keycard Manifesto (press.logos.co/article/keycar…) is refreshingly different. It rejects the monolithic lock-in model where consumer is left with a feel-good-factor of self-custody without having lifted the hood to see what really backs this promise. Instead, @Keycard_ is laying it out all in the open, making its core principles transparent as they have guided each aspect of the design of this hardware wallet: 1. Self-Custody as the Foundation of Digital Sovereignty Self-custody is not just about securing assets — it is the cornerstone of digital freedom. It enables people to participate in networks, governance, and digital communities on their own terms, without intermediaries. Core promise: “Your keys, your rules” — keys must work with any wallet willing to support Keycard and without lock-in. 2. Modularity Over Monolithic Design Traditional hardware wallets are flawed because they are monolithic (one device does storage, signing, display, and logic — creating a large attack surface). Keycard separates concerns: the secure element (Keycard) only holds keys and signs; the interface (Shell) handles display and input. Core promise: More secure, modular and composable systems through clean separation of roles. 3. Radical Openness and Transparency Tools for self-custody must be transparent, resilient, and open — available to all and owned by no one. Everything (applet, hardware designs, schematics, casing) is released as public goods under permissive licenses (e.g., MIT) and uses common self-replaceable components like off the shelf battery. Core promise: Anyone can audit, fork, improve, assemble, or integrate Keycard. It is a shared foundation, not a proprietary product. 4. Minimal, Durable, and Battle-Tested Security The secure element should be minimal and isolated — doing one thing well (hold keys + sign). Keycard uses proven smart card technology (JavaCard), replaceable batteries, lasts over a decade, tamper-resistant, secure (EAL6+), and simple NFC tap or QR-based signing. Core promise: Eliminate common hardware wallet failures (fragile batteries, opaque firmware, vendor control, single points of failure) while keeping security high and maintenance near zero. 5. True Portability and Interoperability Keys should feel personal and talismanic — carry one card in your wallet for daily use, another as a cold vault. Support open standards (ERC-4527, UR2.0, NFC) so it works across mobile, desktop, EVM, Bitcoin, and future systems without pairing or drivers. Core promise: Seamless, permissionless, use with any 15+ popular wallet apps - not just one vendor app. 6. Community-Owned Public Infrastructure Keycard is a starting point for a permissionless hardware stack. It invites builders, manufacturers, and self-sovereign network projects to adopt, extend, and contribute. Core promise: Foster a community of tinkerers and projects; open trust without central gatekeepers. In a world of abstract seed phrases and black-box gadgets, there's something profoundly human about the design of Keycard Shell and Keycard. Self-custody has always been about more than security. It's about refusing to outsource the core of your freedom. Keycard feels alive with that spirit: minimal where it matters, open where it counts, and fiercely committed to putting real control back in our hands—literally. If you're tired of "secure" devices that still feel like someone else's property, read the manifesto and see the difference: press.logos.co/article/keycar… Explore Keycard at keycard.tech 🫵Your keys. Your rules. Your move.

@KeystoneWallet @nixorokish @tervelix @borislavItskovv @ambire @imTokenOfficial Not sure what happened here of course .... still lot of hardware wallets die because their battery die first. That's why hardware wallets should have easily replaceable battery 👉 keycard.tech

@nixorokish @tervelix @borislavItskovv @Keycard_ @ambire @imTokenOfficial So sorry for this. Could you please raise a ticket here? keystonewallet.atlassian.net/servicedesk/cu… Our CS team will help you on this!

using my Keycard wallet for the first time. haven't gotten far but i like it a lot so far! hey @keycard_ - wen @ambire in the software wallet options?

@Keycard_ is about taking freedom to the next level. In this podcast, @glgrau shares why we built @Keycard_ and what's at stake for self custody.