{"id":147738,"date":"2026-04-06T18:34:47","date_gmt":"2026-04-06T18:34:47","guid":{"rendered":"https:\/\/mycryptomania.com\/?p=147738"},"modified":"2026-04-06T18:34:47","modified_gmt":"2026-04-06T18:34:47","slug":"secondhqs-bark-boasts-new-era-of-bitcoin-payments-drawing-in-former-blockstream-developers","status":"publish","type":"post","link":"https:\/\/mycryptomania.com\/?p=147738","title":{"rendered":"SecondHQ\u2019s Bark Boasts New era of Bitcoin Payments, drawing in former Blockstream developers"},"content":{"rendered":"

Bitcoin Magazine<\/a><\/p>\n

SecondHQ\u2019s Bark Boasts New era of Bitcoin Payments, drawing in former Blockstream developers<\/a><\/p>\n

<\/div>\n

SecondHQ, a new Bitcoin development lab, has gained attention recently as it drew in yet another former Blockstream employee known as \u201cGrubles\u201d, with over 8 years of engineering at the company. Bark, SecondHQ\u2019s lead product, promises to deliver a next-generation \u201cFast, low-fee, self-custodial\u201d wallet.\u00a0<\/p>\n

\n

After 8+ years, today is my last day at Blockstream. <\/p>\n

It\u2019s been an incredible opportunity to work with such a world class team on both the marketing and engineering side, and words alone do not convey my gratitude for the experience. <\/p>\n

Even though I\u2019m leaving, I\u2019m super excited\u2026<\/p>\n

\u2014 grubles (@notgrubles) March 3, 2026<\/a>\n<\/p><\/div>\n

Alongside Grubles, other former Blockstream employees have joined the SecondHQ, such as Neil Woodfine (CMO), Steven Roose (CEO), and Erik De Smedt (CTO). The lab is currently focused on the cutting-edge of end-user Bitcoin wallet technology. In this niche of the industry, the Ark protocol is the new kid on the block, a layer two payments protocol that makes different trade-offs than the Lightning Network to deliver end users scalable self-custody and payments features at a low cost. Bark is SecondHQ\u2019s custom implementation of the Ark protocol, designed for interoperability with the Lightning Network.\u00a0<\/p>\n

\u201cThe technique used for Bark is different from payment channels in Lightning, but the two are actually very complementary.\u201d Grubles told Bitcoin Magazine in an exclusive interview, adding that \u201cAt Second, we\u2019ve chosen to build an Ark that is focused entirely on making Bitcoin onboarding and payments excellent.\u201d Their website describes an Ark-to-Lightning bridge that lets users pay Lightning invoices directly from an Ark balance with no channels, liquidity, or LSPs required. Handled atomically.<\/p>\n

According to Grubles, the company has raised 5.1M from a private investor, with a team of 11 people working on Bark. Deep technical documentation about the project can be found at second.tech<\/a>, with the main net launch expected \u201cSoon\u201d.\u00a0<\/p>\n

Interested users can test out making Bark payments on Signet. \u201cI highly recommend doing so since it\u2019s such a shift in the way we can do onboarding and payments,\u201d said Grubles, encouraging early adopters to test out the tech.\u00a0<\/p>\n

Scaling Bitcoin Self-Custody<\/h2>\n

The most impressive claim made by Bark is the promise of self-custody at a low cost. While it is relatively trivial to scale Bitcoin payments in a custodial manner, as demonstrated by apps like Wallet of Satoshi, or as is being done now by the payments giant Cash App. Delivering self-custody for relatively small amounts of value to millions of people is another matter entirely.<\/p>\n

Onchain Bitcoin can handle roughly 7 transactions of per second, which does not scale to too many users if they are all doing maxinym self custody onchain transactions multiple times a day. To quote Knifefight\u2019s excellent article<\/a> on the matter on Bitcoin Magazine, tittled \u201cFree As In Freedom Is Not Free As In Beer\u201d; \u201cBitcoin confirms ~0.4M transactions\/day. That\u2019s one transaction\/person every ~55 years, assuming no one is born or dies while waiting.\u201d Onboarding users with onchain Bitcoin can also be rather awkward, as wallets correctly signal that deposits made to new users are pending confirmation until confirmed, which can take up to 30 minutes while blocks are mined.\u00a0<\/p>\n

To address the challenges of scaling Bitcoin payments to the whole world, while retaining the cypherpunk and decentralization qualities of onchain self-custody, the Lightning Network was developed, and for the most part, it has worked, but with significant trade-offs. Self hosting a sovereign Lightning node, \u2014 while easier than ever today \u2014 still requires a significant learning curve, or specialized hardware that pushes all the right buttons for you. Both of these barriers to entry are too much for most people who don\u2019t care about tech and just need to be able to pay a bill securely.<\/p>\n

Mobile wallets like Phoenix have taken Lightning Network-style self-custody to end users, but with some caveats. Users need to trust Phoenix with some extreme scenarios, while they also give up a significant amount of privacy, since Acinq, the app developer, needs to know user balances pseudonymously to process transactions. Users are also locked into Phoenix as a liquidity provider, paying often higher fees than custodial lightning alternatives. The app is non KYCed, and offers users self-custody recovery paths, and an excellent feature set<\/a>, but still falls short of the user experience expected from cash, where onboarding is as easy as handing a new user some paper money \u2014 no liquidity challenges, channel managment or onboarding fees \u2014 and payment is as easy handing over a bill and calculating the cash back for change.<\/p>\n

Phoenix specifically works very well after users have been onboarded, but the process can cost over $10 dollars in SATS and take over 30 minutes, which is too high a cost when trying to sell Bitcoin as digital cash, and trying to onboard new people on the spot.<\/p>\n

Other companies have attempted to solve these scaling and user experience challenges by leveraging Blockstream\u2019s Liquid Network, an international federation of Bitcoin corporations that operate an alternative Bitcoin-compatible blockchain with fast block times and much larger on-chain capacity. Wallets like Bull Bitcoin or Aqua onboard users with Liquid\u2019s LBTC, which can take a minute or less to confirm a transaction and then offer them a built-in swap exchange to onchain BTC, or the Lightning Network for payments compatible with the broader Bitcoin market.\u00a0<\/p>\n

Both of these solutions work ok, but Bark believes they can do better. The reasonable self-custody recovery paths that onchain Bitcoin users know and love, with the instant payment velocity of the Lightning Network, are both delivered upon app download to users, without the onboarding roadblocks of a Liquid side chain or Lightning channel management.\u00a0<\/p>\n

\u201cI think the UI for Bark wallets will be simplified in comparison, considering how you won\u2019t need to differentiate between L-BTC and BTC,\u201d said Grubles of current Liquid and Lightning solutions. \u201cThis is important when thinking of onboarding new Bitcoin users. You don\u2019t want to bombard them with information that can be confusing.\u201d<\/p>\n

\u201cDon\u2019t get me wrong, we love Lightning,\u201d added Grubles, explaining that \u201cMany of us at Second have worked on projects like Blockstream\u2019s Core Lightning or are currently working on things like the rust-lightning library\u2026So I do not say it lightly that Lightning is in Second\u2019s DNA. With a Bark wallet, you can receive some bitcoin and begin doing Lightning payments literally in seconds. All of the liquidity micromanagement is gone. The onboarding potential is huge, and a large reason why I was attracted to SecondHQ and the technology in Bark.\u201d\u00a0<\/p>\n

The Virtual UTXO<\/h2>\n

As an implementation of the Ark protocol, SecondHQ\u2019s Bark lets users pay each other with Virtual Unspent Transaction Outputs, or vUTXOs. Shinobi, the Technical Writer for Bitcoin Magazine, wrote about the Ark protocol in 2025<\/a> in detail, explaining that vUTXOs \u201care simply pre-signed transactions that guarantee the creation of a real UTXO<\/a> under the unilateral control of a user once submitted onchain, but are otherwise held offchain.\u201d<\/p>\n

\u201cThere are other exciting things you can do with VTXOs, such as mass payouts,\u201d said Grubles of the scalability of Bark. \u201cImagine you\u2019re an employer and need to process payroll. That\u2019s something you can do with instant finality and low fees using Bark. Mining pools could also offer more frequent payouts for their clients instead of forcing them to wait a long time because onchain fees can be high.\u201d<\/p>\n

These vUTXOs function in a similar way as Lightning Network transactions, moving offchain with an option to settle to the main Bitcoin blockchain when needed. Though unlike the Lightning Network, each Ark implementation has a centralized coordination server that enhances the service, this is the main trade-off made by Ark-style protocols, and its risks are mitigated by moving all self-custody-related power to the end user in what is often described as \u201cunilateral exit\u201d capabilities.\u00a0<\/p>\n

Shinobi further explained the trade-offs of Ark, saying, \u201cThe protocol depends on a central coordinating server in order to function properly, but despite that, it is able to provide the same functionality and security guarantees that the Lightning Network does.\u201d Similar to Lightning, self-custody is governed by a kind of smart contract with multiple people involved and a time constraint, in this case, the Ark operators, each user, and a round to refresh vUTXO\u2019s every month or two. \u201cAs long as a user stays online during the required time period,\u201d Shinobi adds, \u201c(unless they choose to trust the operator for short periods of time) every user is capable of unilaterally exiting the Ark system at any time and taking back full unilateral control of their funds on-chain.\u201d<\/p>\n

This unilateral exit is the very definition of self-custody in the context of Bitcoin. By enabling it offchain, it bypasses the constraints of Bitcoin\u2019s block size, respecting the decentralization of the network, so users can run full nodes, audit the full supply and integrity of the chain, but also access unprecedented levels of sovereignty over their money, even in a future where the fees are high and the blocks are full.\u00a0<\/p>\n

Grubles believes the time constraint in Bark is not only manageable but more lenient than that of the Lightning Network; \u201cThere are real tradeoffs like with any scaling solution. Wallets need to come online at least once a month (though Lightning technically requires always-on to be secure). Emergency exits require multiple onchain transactions and can be expensive, but cooperative offboards are the normal path,\u201d adding that \u201cI think the breakthrough is going to come down to execution. As long as we\u2019re managing our Lightning gateway well and have a reliable SDK, the ingredients are there to deliver a bitcoin payment UX that beats everything else out there. Our expectation is that Bark becomes the default way end users engage with the Lightning Network.\u201d<\/p>\n\n

This post SecondHQ\u2019s Bark Boasts New era of Bitcoin Payments, drawing in former Blockstream developers<\/a> first appeared on Bitcoin Magazine<\/a> and is written by Juan Galt<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"

Bitcoin Magazine SecondHQ\u2019s Bark Boasts New era of Bitcoin Payments, drawing in former Blockstream developers SecondHQ, a new Bitcoin development lab, has gained attention recently as it drew in yet another former Blockstream employee known as \u201cGrubles\u201d, with over 8 years of engineering at the company. Bark, SecondHQ\u2019s lead product, promises to deliver a next-generation […]<\/p>\n","protected":false},"author":0,"featured_media":147739,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-147738","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-discovery"],"_links":{"self":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/posts\/147738"}],"collection":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=147738"}],"version-history":[{"count":0,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/posts\/147738\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/media\/147739"}],"wp:attachment":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=147738"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=147738"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=147738"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}