ArtForz-Timewarp Attack on Bitcoin Explained

Summary: In this episode, Christine D. Kim interviews Blockspace co-founder Drew Van der Werff about Ethereum’s blockspace market. Since the Merge, Ethereum’s transition to proof-of-stake, the blockspace market has become increasingly centralized, with a few sophisticated block builders publishing most blocks. To combat builder centralization, Drew’s team at Blockspace has pioneered a new out-of-protocol software called multi-party block construction (MPBC), which lets builders collaborate on publishing a block and split block rewards without sharing or revealing transaction order flow, except to trusted MPBC operators. Drew explains MPBC’s benefits and drawbacks, and its adoption among builders since it went live in September 2026.This episode was recorded on November 4, 2026. Timestamps:(1:50) Drew’s background in Ethereum (9:50) Why Drew gravitated to Ethereum core protocol development(16:53) Overview of Commit-Boost(23:31) Concerns about ePBS’ impact on builder centralization(33:57) How MPBC addresses builder centralization(37:25) The role of exclusive order flow in builder centralization(53:04) The drawbacks of MPBC(1:01:21) The end game for Ethereum’s blockspace market Show links: Drew’s X profile (https://x.com/DrewVdW) Blockspace Forum blog post on block bid selection options in Glamsterdam (https://blockspace.forum/takes/keep-the-latest-bid.html) Blockspace Forum MPBC data dashboard (https://docs.blockspace.forum/mpbc/live-metrics/#overview) Understanding ePBS Through the Lens of Game Theory w/ Mike Neuder (https://www.youtube.com/watch?v=2uCP53OfPls&t=2s) Unbundling Staking Towards Rainbow Staking by Barnabe Monnot (https://ethresear.ch/t/unbundling-staking-towards-rainbow-staking/18683)Enjoying this content? Subscribe to the newsletter: https://christinedkim.substack.com/ Watch on YouTube: https://www.youtube.com/@ready4merge Follow on X: https://x.com/ready4mergeInterested in sponsoring the show? [email protected]  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

In this episode, Christine D. Kim interviews Brandon Black (aka reardoncode), the lead maintainer of rbitcoin, an alternative Bitcoin client written in Rust. Brandon shares how he first learned about Bitcoin on Slashdot in 2009 and what led him to get involved in Bitcoin development in 2017. He also discusses what prompted him to build rbitcoin, arguing that Bitcoin’s consensus rules shouldn’t be defined by 15-year-old C++ code, and that LLM tools have made specifying and fuzz-testing Bitcoin’s consensus code far more tractable. The conversation also covers how rbitcoin differs from Bitcoin Core and other Bitcoin clients, and which consensus changes Brandon thinks Bitcoin is most likely to adopt in the near future, starting with BIP-448, Taproot-native (Re)bindable Transactions. This episode was recorded on October 28, 2026. Timestamps:(1:45) Brandon’s journey into Bitcoin development(7:30) Why Brandon is working on rbitcoin(20:05) The pivotal role of AI in rbitcoin development (21:46) What differentiates rbitcoin from Bitcoin Core(23:44) How rbitcoin is funded(30:53) Brandon’s view on Bitcoin consensus changes(36:54) Rapid-fire question roundShow links: Brandon’s X profile (https://x.com/reardencode)rbitcoin GitHub (https://github.com/reardencode/rbitcoin)BIP-448, Taproot-native (Re)bindable Transactions (https://bips.dev/448/)  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

In this episode, EthCoordinate’s Nixo Rokish and the Ethereum Foundation’s Antonio Sanso join Christine D. Kim to discuss Ethereum’s post-quantum roadmap.Together, they discuss why Ethereum needs post-quantum security and which parts of the protocol need it. They also discuss how PQ protocol changes will affect end-users and validators. Finally, Antonio shares his views on the post-quantum upgrade timeline and the concrete goals he hopes his team at the Foundation can reach for the I-star hard fork. This episode was recorded on October 21, 2026. Timestamps:(1:00) Antonio’s introduction(1:48) Glamsterdam & Hegota updates(7:09) Where Ethereum needs post-quantum security (16:13) Why Ethereum needs post-quantum security (20:45) The role of zero-knowledge proofs in PQ security (22:53) Ethereum’s PQ roadmap explained(32:55) How the PQ migration impacts end-users(44:11) How the PQ migration impacts validators Show links: Hoodi testnet cancellation (https://christinedkim.substack.com/p/acde-248) Ethereum strawmap (https://strawmap.org/) Antonio’s X account (https://x.com/asanso) Vitalik’s X post on EIP-8288 (https://x.com/VitalikButerin/status/2112032009413439704?s=20)  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

In this episode, Christine D. Kim interviews OpenSats’ Calvin Kim and Vinteum’s Davidson Souza about their work on the Utreexo project. They discuss recent breakthroughs in their research on scaling Bitcoin and progress in implementing Utreexo in alternative clients like Floresta and BTCD. They also discuss AI’s impact on their work and Bitcoin software development more broadly.This episode was recorded on October 13, 2026. Timestamps:(1:34) Davidson Souza introduction(12:45) What differentiates Floresta as a Bitcoin client(19:15) The final state of Utreexo(26:03) What’s next for the Utreexo project(32:19) Why Utreexo still does not need a soft fork(41:33) Concerns about AI and post-quantum(50:57) Best practices for using AI in open-source developmentShow links: - Meet the Devs Interview w/Calvin Kim (https://christinedkim.substack.com/p/podcast-ep-12) Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

Summary: In this episode, Christine D. Kim and Nixo Rokish chat with Mike Neuder, a PhD student at Princeton studying blockchain design and economics. Together, they discuss the design behind enshrined proposer-builder separation (ePBS), one of the main features that will be activated on Ethereum through the Glamsterdam upgrade. Mike argues for understanding ePBS through the lens of game theory and the hidden incentives that may drive how MEV actors interact with the feature. This episode was recorded on October 6, 2026. Timestamps:(00:29) Introducing Mike Neuder, a PhD student at Princeton(3:47) Glamsterdam testing updates(6:09) How block proposals work today(10:27) How ePBS changes things(17:41) Why trusted payments were built into ePBS(19:20) The role of relays in ePBS(25:21) The role of MEV-Boost in ePBS(31:24) Why the focus of ePBS shifted to scalability(34:57) The free option problem in ePBS(55:08) What core devs need to know about ePBS(56:46) What MEV stakeholders need to know about ePBS(59:51) Was ePBS worth its complexity? Enjoying this content? Subscribe to the newsletter: https://christinedkim.substack.com/ Watch on YouTube: https://www.youtube.com/@ready4merge Follow on X: https://x.com/ready4mergeInterested in sponsoring the show? [email protected]  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

Summary: In this episode, Christine D. Kim and Murch discuss the intricacies of the ArtForz-Timewarp attack vector and the consensus changes required on Bitcoin to fix it. They also briefly discuss the governance process behind Bitcoin soft forks and the latest updates to the forthcoming Bitcoin Core v32 release. This episode was recorded on September 25, 2026. Timestamps:(1:04) Bitcoin Core v32 Release Updates(10:15) ArtForz-Timewarp Attack Explained(23:01) The likelihood of a timewarp attack(30:35) BIP-54’s likelihood of activationEnjoying this content? Subscribe to the newsletter: https://christinedkim.substack.com/ Watch on YouTube: https://www.youtube.com/@ready4merge Follow on X: https://x.com/ready4mergeInterested in sponsoring the show? [email protected]  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

Summary: In this episode, Christine D. Kim from Protocol Watch and Nixo Rokish from EthCoordinate discuss the arguments for and against changes to Ethereum issuance. Rokish underscores the importance of changes that not only reduce issuance but, under certain conditions, drive it to zero. Kim explains why changes to issuance without social consensus would be detrimental to Ethereum's value.This episode was recorded on September 23, 2026. Timestamps:(1:20) Glamsterdam and Hegota updates(9:51) Nixo’s stance on issuance(19:53) Arguments against issuance changes(29:53) Why EIP-8363 most likely won’t get included in Hegota(35:33) Christine’s stance on social consensus Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

Summary: In this episode, Christine is joined by Murch of Localhost Research for a Bitcoin development update. They kick off the episode with brief remarks on the differences in client funding dynamics between Bitcoin and Ethereum. Murch then walks through the Bitcoin Core v32 branch-off, including the per-release updates to assumevalid and other defaults. Finally, Murch and Christine discuss software security in the age of AI, covering how Bitcoin Core contributors are adapting their workflows to use AI at the individual-contributor and project level.This episode was recorded on September 16, 2026. Timestamps:(0:50) Plug for TabConf 2026(3:24) Murch’s views on the Ethereum client funding crisis(9:23) Bitcoin Core v32 branch off (20:37) AI’s role in the Bitcoin Core release cycle(28:45) Bitcoin Core’s response to the influx of AI-generated security reportsEnjoying this content? Subscribe to the newsletter: https://christinedkim.substack.com/ Watch on YouTube: https://www.youtube.com/@ready4merge Follow on X: https://x.com/ready4mergeInterested in sponsoring the show? [email protected]  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

In this episode, Christine and Nixo discuss the timeline for the Ethereum Glamsterdam upgrade and next steps for scoping out Hegotá. Nixo shares her expectations for a mainnet Glamsterdam activation in December and her views on how client team funding may impact the size of future Ethereum forks. This episode was recorded on September 9, 2026. Timestamps:(1:15) Nixo’s career before crypto(3:47) How to prepare for Glamsterdam(6:48) Glamsterdam mainnet ETA(15:49) The Hegota fork scoping process(23:14) The status of Frame Txs in Hegota(33:39) Client team funding impacts on HegotaShow links: - Ethereum public testnets overview (https://forkcast.org/networks/)Enjoying this content? Subscribe to the newsletter: https://christinedkim.substack.com/ Watch on YouTube: https://www.youtube.com/@ready4merge Follow on X: https://x.com/ready4mergeInterested in sponsoring the show? [email protected]  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe

In this episode, Christine D. Kim introduces the show’s new co-hosts for the season, Nixo from EthCoordinate and Murch from Localhost Research. Together, they discuss the show's vision, the topics they expect to cover over the next several weeks, and how listeners can learn more about Bitcoin and Ethereum development. This episode was recorded on September 2, 2026. Timestamps:3:36 Introducing Nixo7:23 Introducing Murch10:26 Why tune in for Season 2? 26:12 What topics will be discussed on this season32:21 Bitcoin and Ethereum development resources Enjoying this content? Subscribe to the newsletter: https://christinedkim.substack.com/ Watch on YouTube: https://www.youtube.com/@ready4merge Follow on X: https://x.com/ready4mergeInterested in sponsoring the show? [email protected]  Get full access to Christine D. Kim at christinedkim.substack.com/subscribe