Bitcoin Optech Podcast

Mark “Murch” Erhardt and Mike Schmidt are joined by Abubakar Sadiq Ismail, Gregory Sanders, and Daniel Roberts to discuss ⁠Newsletter #336⁠. News Investigating mining pool behavior before fixing a Bitcoin Core bug (1:07) Contract-level relative timelocks (15:04) Multiparty LN-Symmetry variant with penalties for limiting published updates (29:06) Releases and release candidates Bitcoin Core 28.1 (39:54) BDK 0.30.1 (40:45) LDK v0.1.0-beta1 (42:01) Notable code and documentation changes Bitcoin Core #28121 (42:22) BDK #1592 (43:14)

Dave Harding and Mike Schmidt are joined by Yuval Kogman, Jeremy Rubin, and Steve Myers to discuss ⁠Newsletter #335⁠. News Deanonymization attacks against centralized coinjoin (1:39) Updated ChillDKG draft (14:09) Changing consensus CTV enhancement opcodes (18:41) Adjusting difficulty beyond 256 bits (31:52) Transitory soft forks for cleanup soft forks (33:44) Quantum computer upgrade path (48:09) Consensus cleanup timewarp grace period (56:10) Releases and release candidates BDK wallet-1.0.0 (1:06:44) LND 0.18.4-beta (1:17:28) Core Lightning v24.11.1 (1:18:13) Bitcoin Core 28.1rc2 (1:18:47) LDK v0.1.0-beta1 (1:19:37) Notable code and documentation changes Bitcoin Core #31223 (1:20:19) Eclair #2888 (1:21:09) LDK #3495 (1:22:35) LDK #3436 (1:24:31) LDK #3435 (1:25:02) LDK #3365 (1:26:04) LDK #3340 (1:26:41) BDK #1670 (1:28:47) BIPs #1689 (1:31:45) BIPs #1697 (1:33:49) BLIPs #52 (1:34:21) BLIPs #54 (1:35:40)

Mark “Murch” Erhardt and Mike Schmidt are joined by Dave Harding, Niklas Gögge, Gloria Zhao, and Rearden to discuss ⁠Newsletter #334: 2024 Year-in-Review Special⁠. January Fee-dependent timelocks (16:18) Optimized contract protocol exits (17:20) LN-Symmetry proof-of-concept implementation (18:22) February Replace by feerate (22:32) Human-readable payment instructions (27:25) Improved ASMap generation (28:09) LN dual funding (32:33) Trustless betting on future feerates (32:56) Summary 2024: Vulnerability disclosures (7:05) March BINANAs and BIPs (33:33) Enhanced feerate estimation (34:41) More efficient transaction sponsorship (46:08) April Consensus cleanup (50:06) Reforming the BIPs process (51:08) Inbound routing fees (53:10) Weak blocks (54:01) Restarting testnet (57:43) Developers arrested (1:00:06) Summary 2024: Cluster mempool (1:01:10) May Silent payments (1:06:51) BitVMX (1:07:37) Anonymous usage tokens (1:09:50) LN channel upgrades (1:12:00) Ecash for pool miners (1:13:33) Miniscript specification (1:14:54) Utreexo beta (1:16:16) June LN payment feasibility and channel depletion (1:18:17) Quantum-resistant transaction signing (1:20:02) Summary 2024: P2P transaction relay (1:20:39) July Blinded paths for BOLT11 invoices (1:31:07) ChillDKG key generation for threshold signatures (1:31:47) BIPs for MuSig and threshold signatures (1:32:18) August Hyperion network simulator (1:33:00) Full RBF (1:33:56) Summary 2024: Covenants and script upgrades (2:08) September Hybrid jamming mitigation tests and tweaks (1:35:10) Shielded CSV (1:38:40) LN offline payments (1:41:22) October BOLT12 offers (1:42:34) Mining interfaces, block withholding, and share validation cost (1:43:13) Summary 2024: Major releases of popular infrastructure projects (1:50:41) November SuperScalar timeout tree channel factories (1:51:19) Fast and cheap low-value offchain payment resolution (1:53:29) Summary 2024: Bitcoin Optech (1:55:17)

Mark “Murch” Erhardt and Mike Schmidt are joined by Dave Harding, /dev/fd0, and Gloria Zhao to discuss Newsletter #333. News Vulnerability allowing theft from LN channels with miner assistance (1:11) Deanonymization vulnerability affecting Wasabi and related software (12:00) Insights into channel depletion (18:12) Poll of opinions about covenant proposals (31:14) Incentive-based pseudo-covenants (41:49) Bitcoin Core developer meeting summaries (46:45) Bitcoin Core PR Review Club Track and use all potential peers for orphan resolution (48:18) Changes to services and client software Java-based HWI released (1:00:32) Saving Satoshi Bitcoin development education game announced (1:01:24) Neovim Bitcoin Script plugin (1:02:19) Proton Wallet adds RBF (1:03:36) Selected Q&A from Bitcoin Stack Exchange How long does Bitcoin Core store forked chains? (1:03:51) What is the point of solo mining pools? (1:05:02) Is there a point to using P2TR over P2WSH if I only want to use the script path? (1:11:17) Releases and release candidates Core Lightning 24.11 (1:13:23) BTCPay Server 2.0.4 (1:16:59) LND 0.18.4-beta.rc2 (1:17:23) Bitcoin Core 28.1RC1 (1:17:44) BDK 1.0.0-beta.6 (1:18:36) Notable code and documentation changes Bitcoin Core #31096 (1:18:58) Bitcoin Core #31175 (1:19:51) Bitcoin Core #31112 (1:21:37) LDK #3446 (1:22:56) Rust Bitcoin #3682 (1:26:13) BTCPay Server #5743 (1:27:17) BDK #1756 (1:30:23) BIPs #1535 (1:31:12) BOLTs #1180 (1:32:33)

Dave Harding and Mike Schmidt are joined by René Pickhardt and Christian Decker to discuss Pickhardt’s ⁠Lightning Network channel depletion research⁠. Summary of Pickhardt's research (1:01) Why look at wealth distributions? (5:45) What can be learned from depletion? (11:38) Circular rebalancing (13:33) What determines where the spanning tree is? (15:28) Mitigating depletion (20:14) Adjacent channels and their impact (26:39) Multiparty channels, channel factories, and Ark (29:52) Hub-and-spoke topology discussion (41:06) What real world data would inform the theoretical? (54:54)

Mark “Murch” Erhardt and Mike Schmidt are joined by Antoine Riard and Antoine Poinsot to discuss ⁠Newsletter #332⁠. News Transaction censorship vulnerability (0:55) Continued discussion about consensus cleanup soft fork proposal (19:20) Releases and release candidates Eclair v0.11.0 (46:45) LDK v0.0.125 (47:26) Core Lightning 24.11rc3 (47:59) LND 0.18.4-beta.rc1 (48:21) Bitcoin Core 28.1RC1 (48:34) Notable code and documentation changes Bitcoin Core #30708 (49:15) Core Lightning #7832 (50:32) LND #8270 (51:36) LND #8390 (52:49) BIPs #1534 (55:49)

Mark “Murch” Erhardt and Mike Schmidt are joined by Anthony Towns to discuss ⁠Newsletter #331⁠. News Lisp dialect for Bitcoin scripting (0:48) Selected Q&A from Bitcoin Stack Exchange How does ColliderScript improve Bitcoin and what features does it enable? (43:24) Why do standardness rules limit transaction weight? (48:10) Is the scriptSig spending an PayToAnchor output expected to always be empty? (56:16) What happens to the unused P2A outputs? (57:13) Why doesn't Bitcoin's PoW algorithm use a chain of lower-difficulty hashes? (1:01:47) Clarification on false value in Script (1:04:38) What is this strange microtransaction in my wallet? (1:06:02) Are there any UTXOs that can not be spent? (1:09:04) Why was BIP34 not implemented via the coinbase tx's locktime or nSequence? (1:13:15) Releases and release candidates Core Lightning 24.11rc2 (1:15:19) BDK 0.30.0 (1:15:49) LND 0.18.4-beta.rc1 (1:16:16) Notable code and documentation changes Bitcoin Core #31122 (1:17:17) Core Lightning #7852 (1:20:25) Core Lightning #7740 (1:21:27) Core Lightning #7719 (1:22:48) Eclair #2935 (1:23:47) LDK #3137 (1:24:34) LND #8337 (1:26:22)

Mark “Murch” Erhardt and Mike Schmidt are joined by ZmnSCPxj, Vojtěch Strnad, Moonsettler, Brandon Black, Ethan Heilman, and Dusty Daemon to discuss Newsletter #330.

Mark “Murch” Erhardt discusses Newsletter #329. News MAD-based offchain payment resolution (OPR) protocol (0:21) Papers about IP-layer censorship of LN payments (3:10) Releases and release candidates BTCPay Server 2.0.3 (6:21) Notable code and documentation changes Bitcoin Core #30592 (8:29) Bitcoin Core #30930 (9:46) LDK #3283 (11:35) LND #7762 (12:31)

Mark “Murch” Erhardt and Gregory Sanders discuss Newsletter #328. News Disclosure of a vulnerability affecting Bitcoin Core versions before 25.1 (0:53) Bitcoin Core PR Review Club Ephemeral Dust (6:54) Releases and release candidates Bitcoin Core 27.2 (14:55) Libsecp256k1 0.6.0 (15:40) Notable code and documentation changes LDK #3360 (17:40) LDK #3207 (18:45)

Mark “Murch” Erhardt and Mike Schmidt are joined by Andrew Toth to discuss ⁠Newsletter #327⁠. News Timeout tree channel factories (0:50) Draft BIP for DLEQ proofs (10:53) Releases and release candidates BTCPay Server 2.0.0 (20:02) Notable code and documentation changes Bitcoin Core #31130 (22:56) LDK #3007 (25:14) BIPs #1676 (27:15)

Dave Harding and Mike Schmidt are joined by ZmnSCPxj to discuss his SuperScalar proposal. Why a deep dive? (0:40) Proposal overview (1:58) Importance of reallocating liquidity (4:13) What about overloading channels with liquidity from the start? (9:42) Discussion of multi-LSP vs single LSP approaches (13:05) Ensuring unilateral exit is possible (15:22) Malicious users forcing unilateral closes (20:21) Decker–Wattenhofer channels vs John Law's tunable penalties (27:11) Decker–Wattenhofer relative lock times impact on users (38:44) Discussion of trustless non-P2P protocol structure (40:01) Contrasting SuperScalar with Ark (44:08) Implementation discussion (48:44)

Mark “Murch” Erhardt and Mike Schmidt are joined by Elle Mouton and Andrew Toth to discuss Newsletter #326. News Updates to the version 1.75 channel announcements proposal (1:36) Draft BIP for sending silent payments with PSBTs (16:28) Selected Q&A from Bitcoin Stack Exchange Duplicate blocks in blk*.dat files? (30:07) How was the structure of pay-to-anchor decided? (32:45) What are the benefits of decoy packets in BIP324? (36:38) Why is the opcode limit 201? (39:20) Will my node relay a transaction if it is below my minimum tx relay fee? (40:31) Why doesn't the Bitcoin Core wallet support BIP69? (42:09) How can I enable testnet4 when using Bitcoin Core 28.0? (44:50) What are the risks of broadcasting a transaction that reveals a `scriptPubKey` using a low-entropy key? (47:33) Releases and release candidates Core Lightning 24.08.2 (52:12) Notable code and documentation changes Eclair #2925 (52:56) LND #9172 (53:37) Rust Bitcoin #2960 (55:47)

Mark “Murch” Erhardt and Mike Schmidt are joined by Olaoluwa Osuntokun and Steven Roose to discuss ⁠Newsletter #325⁠. News LN Summit 2024 notes (0:51) Changes to services and client software Coinbase adds taproot send support (49:03) Dana wallet released (51:53) Kyoto BIP157/158 light client released (53:20) DLC Markets launches on mainnet (1:01:39) Ashigaru wallet announced (1:02:30) DATUM protocol announced (1:03:10) Bark Ark implementation announced (1:03:55) Phoenix v2.4.0 and phoenixd v0.4.0 released (1:11:31) Releases and release candidates BDK 1.0.0-beta.5 (1:12:33) Notable code and documentation changes Bitcoin Core #30955 (1:13:11) Eclair #2927 (1:14:37) Eclair #2922 (1:15:38) LDK #3235 (1:16:30) LND #8183 (1:17:21) Rust Bitcoin #3450 (1:18:09)

Mark “Murch” Erhardt and Mike Schmidt are joined by Antoine Poinsot to discuss ⁠Newsletter #324⁠. News Disclosure of vulnerabilities affecting Bitcoin Core versions before 25.0 (1:09) CVE-2024-38365 btcd consensus failure (11:22) Guide for wallets employing Bitcoin Core 28.0 (23:27) Bitcoin Core PR Review Club Add getorphantxs (27:43) Releases and release candidates Bitcoin Inquisition 28.0 (26:35) BDK 1.0.0-beta.5 (31:39) Notable code and documentation changes Core Lightning #7494 (32:22) Core Lightning #7539 (34:46) LDK #3179 (35:46) LND #8960 (36:56) Libsecp256k1 #1479 (37:38) Rust Bitcoin #2945 (39:29) BIPs #1674 (39:49)

Mark “Murch” Erhardt and Mike Schmidt are joined by Bastien Teinturier to discuss ⁠Newsletter #323⁠. News Impending btcd security disclosure (0:54) Releases and release candidates Bitcoin Core 28.0 (3:11) BDK 1.0.0-beta.5 (15:13) Notable code and documentation changes Bitcoin Core #30043 (20:47) Bitcoin Core #30510 (22:15) Core Lightning #7644 (25:06) Eclair #2848 (26:28) Eclair #2860 (30:57) Eclair #2861 (29:17) Eclair #2875 (31:19) LDK #3303 (40:24) BDK #1616 (41:29) BIPs #1600 (46:02) BOLTs #798 (48:25)

Jon Atack and Mike Schmidt are joined by Gloria Zhao and Jonas Nick to discuss ⁠Newsletter #322⁠. News Disclosure of vulnerability affecting Bitcoin Core versions before 24.0.1 (2:01) Hybrid jamming mitigation testing and changes (17:51) Shielded client-side validation (CSV) (25:28) Draft of updated BIP process (48:47) Selected Q&A from Bitcoin Stack Exchange What specific verifications are done on a fresh Bitcoin TX and in what order? (54:31) Why is my bitcoin directory larger than my pruning data limit setting? (55:42) What do I need to have set up to have `getblocktemplate` work? (58:19) Can a silent payment address body be brute forced? (1:00:02) Why does a tx fail `testmempoolaccept` BIP125 replacement but is accepted by `submitpackage`? (1:01:38) How does the ban score algorithm calculate a ban score for a peer? (1:03:53) Releases and release candidates BDK 1.0.0-beta.4 (1:06:41) Bitcoin Core 28.0rc2 (1:06:57) Notable code and documentation changes Eclair #2909 (1:10:15) LND #9095 (1:11:12) LND #8044 (1:11:55)

Rijndael and Mike Schmidt are joined by Andy Schroder and Virtu to discuss ⁠Newsletter #321⁠. News Proving UTXO set inclusion in zero knowledge (1:47) LN offline payments (11:32) DNS seeding for non-IP addresses (30:00) Changes to services and client software Strike adds BOLT12 support (42:15) BitBox02 adds silent payment support (43:29) The Mempool Open Source Project v3.0.0 released (45:22) ZEUS v0.9.0 released (46:39) Live Wallet adds consolidation support (47:04) Bisq adds Lightning support (48:30) Releases and release candidates HWI 3.1.0 (49:32) Core Lightning 24.08.1 (49:56) BDK 1.0.0-beta.4 (50:27) Bitcoin Core 28.0rc2 (51:04) Notable code and documentation changes Bitcoin Core #28358 (52:23) Bitcoin Core #30286 (53:53) Bitcoin Core #30807 (55:24) LND #8981 (56:36) LDK #3140 (57:34) LDK #3163 (58:50) LDK #3010 (59:40) BDK #1581 (1:00:18) BDK #1561 (1:01:21)

Mark “Murch” Erhardt and Mike Schmidt are joined by Bruno Garcia, Shehzan Maredia, Gloria Zhao, Fabian Jahr, and Gregory Sanders to discuss ⁠Newsletter #320⁠. News Mutation testing for Bitcoin Core (1:39) DLC-based loan contract execution (9:15) Bitcoin Core PR Review Club Testing Bitcoin Core 28.0 Release Candidates (21:08) Releases and release candidates LND v0.18.3-beta (51:33) BDK 1.0.0-beta.2 (53:05) Bitcoin Core 28.0rc1 (53:14) Notable code and documentation changes Bitcoin Core #30509 (53:38) Bitcoin Core #29605 (1:00:52)

Mark “Murch” Erhardt and Mike Schmidt are joined by Filippo Merli, Lorenzo Bonazzi, Matt Corallo, Eric Voskuil, and rkrux to discuss ⁠Newsletter #319⁠. News Stratum v2 extension for fee revenue sharing (1:49) OP_CAT research fund (17:53) Mitigating merkle tree vulnerabilities (22:43) Releases and release candidates Core Lightning 24.08 (55:21) LDK 0.0.124 (57:59) LND v0.18.3-beta.rc2 (1:06:19) BDK 1.0.0-beta.2 (1:06:43) Bitcoin Core 28.0rc1 (1:07:27) Notable code and documentation changes Bitcoin Core #30454 (1:15:05) Bitcoin Core #22838 (1:17:41) Eclair #2865 (1:19:56) LND #9009 (1:21:49) LDK #3268 (1:23:33) BIPs #1657 (1:26:55)