When the show talked about the Coinkite Coldcard — and what it actually said. A fourteen-episode arc that ran from a passing mention in late 2018 to a full hands-on teaching series in the spring and summer of 2019.
World Crypto Network first named the Coldcard in November 2018, as the offline answer to key generation, and again in February 2019 on a round-up of Bitcoin-only hardware. Then, across April, May and July 2019, the network ran a twelve-part hands-on series — hosted by Max Hillebrand — that unbagged the new Mark2, walked through its PIN and duress-wallet design, its encrypted micro-SD backups, air-gapped signing with Electrum and Wasabi, and verified-firmware upgrades. The run closed on July 16, 2019 with an interview of Coldcard's creator, Rodolfo Novak, recorded live at Breaking Bitcoin in Amsterdam.
The Coldcard shows up on WCN in three phases: two early mentions that place it in the Bitcoin-only hardware landscape, the concentrated teaching series in the spring of 2019 around the Mark2 launch, and a July coda pairing it with Wasabi and then meeting its maker.
First mention. The Coldcard is cited as the way to generate and store keys entirely offline, feeding partially-signed transactions out through a software wallet.
Placed on a shortlist of Bitcoin-only gear: "a highly recommended, Bitcoin-only, offline hardware wallet with improved clicky buttons in the Mark2 version."
The Mark2 unboxing. The upgrade story is the new physical clicky buttons; the deeper story is SD-card backups, partially-signed transactions, and the option to physically brick the device's security element.
Power-up and tamper-check, PIN and seed entry done privately, and the passphrase that encrypts the seed so a stolen backup is still useless. Ends on durable metal backups.
Don't trust, verify: download firmware and source from GitHub, check the developer's (Peter Gray's) GPG signature, move it by SD card, and install it offline.
The longest episode of the run — the anti-phishing PIN prefix, the secure element, and the duress wallet: a one-way function where "you can derive the duress wallet from the main wallet, but you can't derive the main wallet from the duress wallet."
The four PINs, spelled out: a main PIN, a secondary-wallet PIN to isolate funds, a duress "honey pot" PIN, and a "brick me" PIN that destroys the device.
Air-gapped signing with Electrum over a microSD card — no USB — and a plug for running your own full node for privacy. Closes with the open-source-entrepreneur giveaway.
Under the hood: a 7-Zip archive, AES-256 in CBC mode, keyed from a 12-word passphrase off the device's true random number generator — plus the honest limitations (filenames aren't encrypted; the PIN isn't in the backup).
The practical companion: seed stored offline on a Bitcoin-only device, and the exact steps to make and encrypt the SD backup.
Into the "Danger Zone" on the Mark II — wiping the seed and restoring it from the encrypted card, proving you keep control as long as the backup exists.
Two verified upgrades built to work together, with GPG-signature checks and the firmware "blessing" step after install.
The "privacy maximalist" setup: keys never leave the Coldcard, everything moves by microSD, and Wasabi handles the watching and broadcasting.
The maker himself, live in Amsterdam: PSBT for offline multi-sig across different wallets, an experimental automated cosigner that enforces spending policies, and a nod to OpenDime.
The through-line of every episode is that the Coldcard does one thing: it keeps a Bitcoin private key on a device that never touches the internet. WCN framed it as the answer to the basic problem that phones and laptops can make good randomness but are exposed online. The device signs, the computer only ever sees a partially-signed transaction. That framing — Bitcoin-only, air-gapped, single-purpose — is the reason the show kept coming back to it over nine months.
The most repeated practical point across the Electrum and Wasabi episodes: move data on a microSD card, not over USB, so the Coldcard stays isolated. The same pattern shows up whether the desktop wallet is Electrum or Wasabi — the card carries an unsigned transaction in and a signed one out, and the keys never leave the device.
Two full episodes went to the PIN system, and it's where the show got most animated. Beyond a main PIN, the Coldcard offers a secondary wallet to isolate funds, a duress PIN that opens a decoy "honey pot" wallet under coercion, and a "brick me" PIN that destroys the device outright. The anti-phishing PIN prefix — the device shows you words only it could know before you finish typing — got singled out as the small design touch that defends against a fake Coldcard. The flip side, stated plainly: there is no recovery for a lost PIN or a lost seed.
The firmware-upgrade episodes are really about a habit. Every upgrade walkthrough — Mark2 firmware, then Cold Card v2.1.1 alongside Wasabi v1.1.6 — spends most of its runtime on verifying a GPG signature before installing anything, and on the device's own "blessing" step that confirms signed firmware after the fact. WCN treated verification as the point, not the footnote.
The encrypted-SD-backup episodes are the most technical of the run: a 7-Zip archive under AES-256-CBC, keyed from a twelve-word passphrase generated by the device's true random number generator, restorable to any Coldcard with just that passphrase. Notably, WCN also aired the limitations — filenames in the archive aren't encrypted and the PIN isn't stored in the backup — rather than presenting the feature as flawless.
The arc closes by handing the mic to Rodolfo Novak of Coinkite at Breaking Bitcoin in Amsterdam. The forward-looking themes there — PSBT enabling offline multi-signature across different wallet brands, and an experimental automated cosigner that enforces custom spending policies for remote or institutional use — are the ideas that would define hardware-wallet design for years after. WCN was documenting them as they were announced.