Second

Double changelog today for bark-0.1.0 (you know we’re getting closer to mainnet when the “beta” tag is dropped!). Highlights include event-driven notifications replacing polling, a fee estimation API for all operation types, Tor connectivity, barkd security hardening with auth tokens and CORS, HTLC preimage recovery from on-chain exits, and WASM compilation for browser-based Ark wallets.

Our technical docs just got a whole lot better. New platform, getting started guides for Rust, Go, React Native, and more, an API reference, and possibly the most comprehensive explanations on protocol mechanics for any bitcoin layer 2 out there. The new docs also come with an AI assistant and MCP server (table stakes at this point) to make building on Bark with Claude Code/Cursor even easier. And, we now have DARK MODE.

We've released beta.8. Bark servers now support fees across all operations, and yes, that means we've published a fee schedule for the Second server! Other highlights: a new Watchman component for unified coin sweeping (our last big dependency for going live), server pubkey pinning for wallet security, resilient maintenance that no longer bails on the first error, idempotent Lightning receive claims, and round event replay so mobile wallets can join rounds already in progress.

Christoph Ono's Arké wallet keeps getting better. This is what happens when you unleash a designer armed with agents and the Bark SDK.

Bark makes it ridiculously easy to build bitcoin wallet apps that supports on-chain, Lightning, and Ark payments. All self-custodial.

We've started fuzz testing Bark, a technique that throws semi-random inputs at software to find bugs you'd never think to look for. It already caught one: a malformed message could have crashed the server by requesting an oversized memory allocation. That's now patched, and the fuzzer runs 24/7 alongside a growing library of test vectors. Server uptime has to be watertight on Bark—the payments must flow!

We've redesigned how Bark-based wallets get their updates. The new unified mailbox replaces per-address polling with a single feed for all wallet notifications (Ark and Lightning payments, refreshes, and more) with support for real-time push subscriptions. One endpoint, checkpoint-based sync, and delegated notification auth for mobile. Available now in Bark. https://lnkd.in/gmiUygMm

We've released bark and captaind 0.1.0-beta.7 with a focus on mobile developer experience and push notification infrastructure. The headline feature: a unified mailbox system that consolidates all incoming VTXOs into a single delivery channel, laying the groundwork for notification systems that alert users when they receive funds. Warning: protocol encoding changes require fresh databases—no upgrade path from previous versions.

We've released bark-0.1.0-beta.6 featuring hArk (Hash-lock Ark), a major protocol evolution that eliminates synchronous interactivity during rounds. Previously, all round participants receiving new VTXOs had to be online simultaneously to sign intermediate transactions. hArk removes this requirement—the server generates a unique secret for each VTXO, and participants can claim asynchronously after signing a forfeit transaction. hArk also enables efficient consolidation of multiple VTXOs into a single output and reduces server costs during malicious exit scenarios. Note: Wallets created before this release require migration due to security upgrades with hardened key derivations. Create a new wallet and transfer funds before upgrading.

Highlights from our recent beta releases (bark 0.1.0-beta.3 to beta.5): The biggest addition is barkd—a wallet daemon with RESTful API for node runners and businesses wanting simple automation. We've also made ark-lib WASM-compatible for web environments, replaced the arkoor-depth limitation with checkpoints, and improved Lightning payment reliability. Changelog with more details: https://lnkd.in/gq_S6GpT