Sparrow adds stealth payments

Other (15)

• Arcrox proposed that wallets stop signaling opt-in RBF, noting that Bitcoin Core V28 made full RBF the default, rendering BIP-125 signaling redundant. However, the proposal was withdrawn to maintain fingerprinting homogeneity, as over 75% of transactions currently signal replaceability.
• Merch explained that BIP-125 was introduced in 2015 as opt-in RBF, but the network's default behavior shifted to accepting all replacements with higher fees, making all transactions replaceable regardless of the signal. Merch recommends `max_minus_two` as the best practice default for the input sequence field.
• Arcrox intends to remove the `replaceable` option from Bitcoin Core RPCs, arguing the concept of RBF signaling is outdated and the option serves no clear purpose, despite the default sequence value remaining unchanged to avoid fingerprinting.
• Roland announced Albi Hub 1.23.0, a self-custodial Lightning wallet built on LDK, now featuring Just-in-Time (JIT) channels. JIT channels allow users to receive payments without pre-purchasing liquidity; a small fee from the payment automatically opens a channel.
• Albi Hub's experimental ARK backend from Sikin offers a cheaper alternative to Lightning for casual users making fewer than 100 payments, by eliminating the initial investment of opening a channel. Roland also highlighted ARK's open-source SDK for building Nostr Wallet Connect apps.
• Stephen confirmed Sikin's Bark, an ARK implementation, went live on Bitcoin mainnet weeks ago, following a private beta and nearly a year on signet. He noted the protocol is trustless, allowing users to unilaterally exit on-chain if the server misbehaves.
• Stephen emphasized that ARK provides an alternative for small-scale custodial wallets seeking non-custodial solutions due to legal difficulties, offering good UX without the complexities of channel management. Integrators include Noah Wallet, ROK, and a BitC Pay server plugin.
• Stephen explained that ARK functions as a graduated wallet for small to medium balances, supporting direct on-chain off-boarding for savings. While exit costs may be high for tiny balances, the protocol prevents server theft, and higher balances make exits economically reasonable.
• Stephen detailed ARK's liquidity management: the server temporarily fronts liquidity during VTXO refreshes. A progressive fee schedule incentivizes users to refresh closer to the 28-day expiry, minimizing server-fronted liquidity, with HTLC-based VTXOs expiring in 4-5 days.
• Bitcoin Core #35221 introduces BIP 434 (Peer Feature Negotiation Framework), adding a new `feature` P2P message type for nodes to advertise optional peer features. Merch noted the P2P protocol version incremented to 70,017, streamlining future feature communication.
• Bitcoin Core #35254 improves memory hygiene by wiping key derivation material from stack buffers (`Rkey`, `temp`) after use, particularly for BIP32 and BIP324 key derivation. Bitcoin Core #35498 fixes a race condition during block fetching by locking `cs_main` to prevent simultaneous peer disconnections.
• Eclair #33318 resolves a splicing edge case where a reconnecting node would fail to send `splice_lock` after detecting the splice had locked but before receiving the peer's `channel_reestablished` message, which previously led to forced closes.
• LND #7858 begins implementing Bolt 12 by adding foundational infrastructure, including a new message type, codec package, and TLV structures. This work follows LND's recent release that included Onion messages, which are crucial for Bolt 12.
• Rust Bitcoin #6321 fixes a denial-of-service vulnerability where an attacker could declare an excessively large witness stack item count (up to 16 MB) with few input bytes, forcing the client to over-allocate memory. The fix now defers allocation until actual witness bytes are received.
• LDK #4685 prepares for Bolt 12 payment proofs by relocating the payer's nonce from the blinded reply path to the payer metadata, aligning with the proposal. This enables payers to regenerate the invoice-specific key for creating payment proofs.

Protocol (6)

• Marty Bent announced Primal now supports video streaming via Zapstream backend, with iOS available, web expected next week, and Android the following week.
• Kieran, Zapstream's lead maintainer, speculated a state-level actor is DDoSing the service with terabits-per-second attacks.
• Marty Bent reported Bitcoin at $108,540, a $2.16 trillion market cap, and a 5.9% upward mining difficulty adjustment estimated for September 4.
• Matt Odell identified a feedback loop where margin calls on MicroStrategy shareholders drive Bitcoin sales, lowering MSTR's price and triggering further margin calls.
• Odell noted MicroStrategy's market-to-net-asset-value ratio compressed to 1.61x after the company reversed guidance and sold common stock despite promising to halt sales below 2.5x.
• Odell argued Bitcoin's fixed supply creates savings value, while its censorship-resistant peer-to-peer cash capability creates spending utility; both functions are necessary for good money.

Safety (1)

• Odell cited a new AI threat detection platform called Gideon that scrapes internet data with an 'Israeli-grade ontology' and routes threats to law enforcement.

Models (1)

• Matt Odell highlighted Anthropic's new terms allowing user chats to be saved for five years and trained on unless users opt-out before September 28.

Agents (1)

• Odell recommended Maple.ai and self-hosted options for private AI, contrasting them with services like Perplexity that immediately request access to Gmail and calendars.

Markets (1)

• Odell observed Nvidia revealed 25% of its year-to-date revenue came from a single client in Singapore, likely a Chinese export circumvention.

Protocol (6)

• Ricardo Spagni argues Bitcoin's early culture (2011-2014) was more innocent and focused on technology, not price speculation or dogma.
• Spagni observed core developers like Greg Maxwell and Peter Todd openly contributing to projects like Monero's RingCT or paid altcoin gigs, reflecting a non-maximalist, collaborative environment.
• Ricardo Spagni criticizes the "bag bias" - investor sentiment affecting development - as the biggest destroyer of tangible technological value in the crypto space.
• Ricardo Spagni describes the harassment of Gloria Zhao and her stepping down as a Bitcoin Core maintainer as a canary in the coal mine for the death of open-source contributor culture.
• Ricardo Spagni compares the anti-spam filter movement (BIP 110/Knots) to the failed NanoMSG fork, saying projects forked on hatred rather than a unified positive vision always fail.
• Ricardo Spagni notes ETF institutions and corporate treasuries obscure their trades by using custodians like Coinbase, making their Bitcoin transactions invisible on-chain.

Stablecoins (1)

• Ricardo Spagni observes USDT on Tron dominates global south payments due to low cost and Binance's dominance, making it the rational choice over crypto for users despite its lack of censorship resistance.

Society (1)

• Ricardo Spagni says he cannot travel outside South Africa due to an ongoing legal battle, referencing his arrest in 2022.