Simple developer solutions for integrating bitcoin payments into your apps. Fast, low-fee, self-custodial. Supports Lightning, Ark, and on-chain.

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SECOND IS NOW ON MAINNET. Bark, our implementation of the Ark protocol, is available for anyone to start making bitcoin payments. Included in the launch are our mainnet Ark server, the Bark SDK, and multiple wallets to try from day one.
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Second team 💙 @FrostsnapTech
Got my new toys to play with this weekend!
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on Bark, you use bitcoin as money without the hard part no Lightning node to run no channels to open no inbound liquidity to manage not the payer on Noah or Arke, not the shop on BTCPay one shared server runs it and everyone keeps their own keys
50% of all hackathon teams used the Bark SDK in their project!
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Ark is onchain UX but actually usable for payments. Wouldn’t surprise me to see more early era Bitcoin ideas reborn on Ark! 🚢
probably fair satoshi dice on bark barkdice.com needs a bark wallet (see below)
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This was my favorite project in the entire hackathon actually. It's an actually useful product that I would use: let your clanker request spends form your phone wallet.
2nd place winner overall of the @btcplusplus Berlin hackathon! 🎉 🏆 By @GBKS @arkebitcoin It’s a Bark MCP Server that automatically connects to your local iPhone Arké app! Agentic payments from your mobile wallet.
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The two Bark challenge winners at @btcplusplus 🎉 🏆 1. Barkade.money by @stutxo : implementing Sapio script into Bark to offer programmability and covenant emulation 2. BarkDice.com by @thesimplekid : a Satoshi dice successor with very interesting payment patterns, reimbursing overpayments and bring-your-own-client policies
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Bitboard Wallet added a visualization of a Bark emergency exit as part of the @btcplusplus hackathon. It's pretty neat!
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50% of all hackathon teams used the Bark SDK in their project!
Entering a contest only to be handed gift cards instead of hard cash is an immediate letdown. Builders want pure currency for their sweat, not restrictive vouchers. That principle is playing out right now at @btcplusplus Berlin. The payments hackathon is running from 1 to 3 October, and @secondhq is putting real skin in the game. They placed a bounty of 1.5 million sats for the best payments app built on Bark. The payout lands directly in the builder's wallet in native sats. The energy in the room is palpable: ➥ @matthewvuk2 from Second called this the biggest cash sponsor prize at the event, with over 100 builders participating. ➥ Bark serves as Second's Ark payments layer, enabling seamless self-custodial checkouts without forcing anyone to babysit a node or channel liquidity. ➥ Second CTO @stevenroose3 is speaking on solving those exact operational pains. ➥ Electrum put up a 1 million sat challenge, but Second pushed the bar higher. Putting up genuine Bitcoin rewards drives real developer adoption.
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Hearing a lot Barking at the hackathon! 👀 👂
1.5M sats available for the best payments app built on Bark. If you're participating in @btcplusplus's hackathon, show us what you can do.
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A good Ark wallet is adversarial by design. Your bark wallet has your back if the server misbehaves.
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I was impressed by this too. We're sponsoring, I gave my own talk about our Ark based product. But even before every talk already had Ark in it. Many people are talking about it. Super excited for the hackathon projects tomorrow!
Every single talk today has Ark in it
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Replying to @matthewvuk2
So much Ark talk now i was finally forced to try out Bark Wallet 🐶🐕
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A highly engaging talk on @secondhq tech to the @FREEMadeiraOrg community. We onboarded the community, showed how simple, cheap and effective using Ark is while keeping control over your own keys. Great to get tough questions and see the community interested.
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1.5M sats available for the best payments app built on Bark. If you're participating in @btcplusplus's hackathon, show us what you can do.
The Hackathon is live!! ⚡️🥳 @secondhq the biggest cash sponsor prize of the whole event. 1.5 million sats, directly sent to you. (~€1104 / $1,253 USD) Bark is the best for payments. Over 100 participants. Let's build!
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. @stevenroose3 gives a Lightning history walkthrough, from opening channels, the outdated LSP model, and how it all leads up to Ark. He walks through the Bark @BtcpayServer plugin, and everything possible with the Bark SDK. Send to on-chain addresses from off-chain balances
Made with AI
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There must be something to this Ark thing. 🤔🤔
Every single talk today has Ark in it
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(@btcplusplus Berlin)
Every single talk today has Ark in it
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The FROST basis for this new design enables composability across the ecosystem, with @bitcoindevkit to power onchain, and Bark (@secondhq) to power the Lightning! @callebtc @btcplusplus
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Opening Keynote from @renepickhardt at @btcplusplus payments edition. He compares Lightning and Ark, how “Ark reorganizes the liquidity problem” “Lightning cannot scale globally” - Rene Pickhardt
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Bitcoiners are still sleeping on @nwc_dev. It can connect your self-custodial LN wallet with apps and enable very real and practical use cases. For example, we use NWC to: - enable your Lightning wallet to spend Bitcoin wherever debit cards are accepted - Sell Bitcoin via NWC and get an instant SEPA bank transfer. - 1-click topups to deposit more Bitcoin from self-custody
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How do Lightning swaps work using Swaptopia? 🏖️ labs.second.tech/swaptopia/
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