● Help test Bitcoin Core 0.17.1RC1: the first release candidate for this maintenance release has been uploaded. This week’s newsletter suggests helping test a Bitcoin Core maintenance release candidate, provides a link to a modern block explorer whose code has been open sourced, and briefly describes a suggestion for signature hashes to optionally cover transaction size. This week’s newsletter announces a security upgrade for C-Lightning, describes a paper and additional research into wallets that accidentally revealed their private keys, and lists some notable code changes in popular Bitcoin infrastructure projects. Notable code changes this week in Bitcoin Core, LND, C-lightning, and libsecp256k1. Notable code changes made in the past week to popular infrastructure projects are also described. The code supports Bitcoin mainnet, Bitcoin testnet, and the Liquid sidechain. ● Modern block explorer open sourced: after recently announcing a new block explorer website, Blockstream has announced the open source release of both its backend and frontend code. It also includes modern features (such as bech32 address support) and a very nice default theme. Bitcoin’s support is at $25,200 and resistance at $25,700. Everything on the Bitcoin blockchain is done by all the users collectively and not by any kind of central figure at a
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So-called cross-chain bridges are tools that allow the transfer of tokens from one blockchain to another. A lot of professionals from the advertising world believe that using the advertising methods and techniques Bitcoin companies are trying to explore the potential available in the industry. Note that this only affects people using the new sighash flag; it doesn’t affect unrelated transactions. These sketches can provide a powerful new way to optimize relay of unconfirmed transactions for the Bitcoin P2P network. For example, youtu.be explained in a blog post the Eltoo smart contract protocol aimed augmenting Lightning Network (LN), Alice and Bob sign each change of balance in a payment channel with this new sighash flag so that, when they want to close the channel, either one of them can use the transaction with the final balance to spend from the transaction with the initial balance. For example, Alice receives some bitcoins to a particular address; she then spends those bitcoins to Bob using the new sighash f
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For example, Alice has elements 1, 2, and 3. Bob has elements 1 and 3. Despite neither knowing which elements the other has, Alice can send Bob a sketch the size of a single element that contains enough information for him reconstruct element 2. If Bob instead has elements 1 and 2 (not 3), the exact same sketch allows him to reconstruct element 3. Alternatively, if Bob sends Alice a sketch based on his two-element set while Alice has her three-element set, she can determine which element Bob is missing and send it to him directly. That may not sound exciting-the rsync tool has done that for over two decades-but libminisketch allows transferring the differences without knowing what they are ahead of time. 2007 adds a new MaxBackoff configuration option that allows changing the longest amount of time the node will wait before giving up attempting to reconnect one of its persistent pe
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2161 adds a small Python library and framework that can be used for writing plugins. The eDIY Website Builder ecommerce software integrates with JIWA and MYOB, and can read common data formats to import your product data quickly. Autopilot is the ability of the software to automatically suggest new channels to open when a user is first connecting to LN or wants additional spending capacity. The default is for channels to be public. The current method simply returns a list of peers with whom it is recommended to open new channels. An early estimate using a simulator indicates combining sketches with shortened transaction identifiers (for relay only) could reduce total transaction propagation bandwidth by a factor of 44x. Sketches also have the potential to provide other desirable features-for example, LN protocol developer Rusty Russell started a thread on the Lightning-Dev mailing list about using them for sending LN routing table updates. The new method allows specifying what data to consider and returns a list of nodes scored by the algorithm (higher scores being better). Alternative recommendation engines can return their own scored recommendations, and the user (or their software) can decide how to aggregate or otherwise use the scores to actually decide which nodes should receive channel open attempts.