🌴 June + July @ Coinkite

TAPSIGNER, BLOCKCLOCK Micro, SATSCHIPS Hardcase & Bitcoin.Review Podcast

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🥵 Hot Bear Market

According to Glassnode, ‘exchange balances are draining at historically high levels,’

Where are all these withdraws going to? Probably in one of our calculators.

DETERMINISTIC OPTIMISM 🌞 @nvk

This is an incredibly interesting bear market, at this rate there is a good chance @Coinkite posts near the same revenue as the 2021 bull year–and more products coming! Being in #Bitcoin as a company for over a decade, we've never seen such a hot bear Thank you for your biz🙏

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🚀New Products

TAPSIGNER now up for grabs and fully compatible with Nunchuck mobile wallets

DETERMINISTIC OPTIMISM 🌞 @nvk

This is how stupid simple/easy/fast NFC multisig co-sining is with @TAPSIGNER and @nunchuk_io @hugohanoi Da Future #Bitcoin UX 🔥🔥🔥 (It would be the same UX for any m-of-n or single sig, or message singing, or authentication) Very affordable hardware is coming…

Listen to the playback of our TAPSIGNER ‘Ask Me Anything’ session

Coinkite @Coinkite

Ask @nvk your questions about using @TAPSIGNER now: https://t.co/RL36o5Yg5l

🕰️ BLOCKCLOCK Micro pre-sale discount ending soon!

👀 BLOCKCLOCK Mini spotted in the wild:

Alex Gladstein 🌋 ⚡ @gladstein

Former Thai Prime Minister Thaksin Shinawatra (overthrown in a military coup) now rocking a blockclock

🧰 HARDCASE for COLDCARD

• Custom protective foam

• Unbranded to keep a low-key profile

• 4.5 x 3.25 x 1"

🎁 10% off Coinkite virtual gift via Bitrefill.com and the Fold app

🖼️ SATSCHIP pre-launch for artists

Bitcoiners don't buy JPEG that anyone can copy! They buy physical works of arts with unforgeable certificate of authentication —NVK

• We leveraged the firmware from the SATSCARD and TAPSIGNER to bring an authenticating solution for artists and art collectors

• Easily embed a flexible 1 inch square NFC chip directly into your physical work of art

• The authenticity of the piece can be verified by anyone, but only the owner can sign a transaction

• SATSCHIP Gallery is now live

🔩 New Tutorials

• MK4 setup tutorial by BTCSessions

• 2 of 2 multisig with 2 x COLDCARD signing devices, and bitcoin-qt as coordinator

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💾 Firmware upgrades

COLDCARD Mk4 5.0.5

BIP-85 derived passwords:

DETERMINISTIC OPTIMISM 🌞 @nvk

BIP85 Passwords coming to @COLDCARDwallet next! github.com/Coldcard/firmw…

• Pick an index number, and COLDCARD will derive a deterministic, strong (136 bit) password for you. It will even type the password by emulating a USB keyboard. See new areas: Settings > Keyboard EMU and Settings > Derive Seed B85 > Passwords.

• Added docs/bip85-passwords.md documenting new BIP-85 passwords and keyboard emulation.

• BIP-85 derived values can now be exported via NFC, in addition to QR code.

• Other enhancement:

  • Allow signing transaction where foreign UTXO(s) are missing. Only applies to cases where partial signatures are being created. Thanks to @straylight-orbit

  • QR Codes are now easier to scan in bright light. Thanks to @russeree for this useful fix!

  • Support import of multisig wallet from descriptor (only sortedmulti, BIP-67). Also support export of multsig wallet as descriptor.

  • Address explorer can show "change" addresses for standard derivation paths for both single and multisig wallet.

  • OP_RETURN is now a known script and is displayed in ascii when possible

• Bugfix:

  • order of multisig wallet registration does NOT matter

  • allow unknown scripts in HSM mode, with warning

CK-Tap Protocol 1.0.5

"CK Tap" is our command line tool for SATSCARD and TAPSIGNER.

This project also contains the public documentation for the NFC protocol used by the cards, and provides a full python library for coders.

Recent changes:

• New best practices docs: https://dev.coinkite.cards/docs/best-practices.html

  • Add ability to derive non hardened derivations w/ library...

  • 'sign_digest' accepts new 'fullpath' parameter where full bip 32

  • Added @SATSCHIP support

  • Shell output for backup cmd improved

  • Added 'card.product_name' string

• CK-TAP React Native Open Library built by the Hexa wallet team claimed the bounty released

• Added ability to derive non hardened derivations with library (not possible with card - card can only derive hardened path components)

• ‘sign_digest’ accepts new ‘fullpath’ parameter where full bip 32 string path can be passed

• Support added for SATSCHIP v1.0.0 product

• Shell output for backup command improved

• Added card.product_name string

• https://satschip.com/gallery and NFC reader + CLI program for artists to submit

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🗞️ News for devs

Coding something amazing, aren’t you?

Leave us a comment about your latest software updates to receive a shout-out on the next 🎙️Bitcoin.Review podcast by NVK feat. ODELL

DETERMINISTIC OPTIMISM 🌞 @nvk

GM 🌞 Building @BitcoinReviewHQ Episode 03 list. Send your project updates: - Telegram t.me/BitcoinReviewP… - GitHub github.com/nvk/bitcoin.re… - Submit Story bicoin.review submit button at the top right - Email pod at bitcoin dot review

Getting SATSCARD into the hands of builders

• To receive a sample, please email us sales@coinkite.com with a bit of information about who you are and what you plan on building with your new SATSCARD

• Shout-out to Mike Kelly for launching a new SATSCARD demo for authenticating into a venue and keeping a bar tap as creditless collateral

  Mike Kelly @NicerInPerson

  Thanks to @DocHex I got hold of a v1.0.0 SATSCARD this morning, which had a couple of important changes. My verifier app now updated, all working and should be on TestFlight in a couple of hours. Here’s me verifying a card has ₿0.005 ($105) sealed in it. Still blows my mind 🤯🏴‍☠️

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✨ Meme Domains

• https://signingdevice.com

• https://bitcoinbinary.org

• https://bitcointreasuries.net

• https://bitcoinuptime.org

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🤝 Join our team

• Mobile Engineer (iOS + Android)

• Podcast and Video Producer (Part-time)

• Web Designer + Coder

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