Bitcoin Optech Podcast

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Níckolas Goline, Optout, Abubakar Sadiq Ismail, and Moonsettler to discuss Newsletter #420 . Action items ● Prepare for an upcoming Core Lightning security release (1:46) News ● Discussion on universal opt-in replay protection (53:54) ● HWI repository to enter maintenance mode (1:24:05) ● Request for comments on using block-range filters (19:06) Releases and release candidates ● BTCPay Server 2.4.3 (1:28:31) ● Eclair 0.14.2 (1:29:09) Notable code and documentation changes ● Bitcoin Core #34075 (31:21) ● Bitcoin Core #35730 (1:32:02) ● Bitcoin Core #35580 (1:34:03) ● Bitcoin Core #35665 (1:38:36) ● Bitcoin Core #35933 (1:43:02) ● Core Lightning #9374 (1:45:58) ● Eclair #3342 (1:47:15) ● Eclair #3321 (1:48:55) ● LND #11008 (1:50:44) ● HWI #841 (1:52:09) ● HWI #849 (1:53:48) ● Rust Bitcoin #6755 (1:55:12)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Bastien Teinturier, Salvatore Ingala, and spacebear to discuss Newsletter #419 . News ● Reorg vulnerability in LND channel closes (1:13) ● Draft BIP for `rawtr()` output script descriptor (1:14:36) Changes to services and client software ● Payjoin Dev Kit (rust-payjoin) 1.0.0 released (55:33) ● Silent Payments sender plugin for Electrum (1:21:41) ● Superscalar implementation announced (1:22:34) ● Cofund multisig wallet announced (1:24:57) ● Lexe adds human-readable addresses and LNURL-withdraw (1:25:55) ● Ledger Bitcoin app 2.5.0 adds human-readable policy descriptions (37:17) ● Bark 0.5.0 released (1:27:34) ● Bitcoin-PIR for private UTXO queries (1:28:16) ● OP_TEMPLATEHASH Ark demonstration (1:29:44) ● libshrincs formally verified hash-based signatures (1:34:00) Notable code and documentation changes ● Bitcoin Core #32784 (1:38:08) ● Bitcoin Core #35797 (1:40:45) ● Bitcoin Core #35531 (1:44:14) ● Bitcoin Core #35889 (1:48:44) ● Bitcoin Core #35605 (1:51:06) ● Eclair #3352 (12:15) ● Eclair #3351 (20:31) ● Eclair #3345 (23:16) ● LND #8754 (1:54:23) ● LND #11065 (1:55:47) ● HWI #842 (1:57:04)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Michael Ford (fanquake) and Martin Zumsande to discuss ⁠Newsletter #418⁠ . News ● Message transfer failure (33:07) ● Static Bitcoin Core binaries available for testing (1:19) ● Replacing per-peer transaction rate-limiting with global rate limits (18:44) Releases and release candidates ● BTCPay Server 2.4.2 (43:16) ● LND v0.21.2-beta (45:45) ● LND v0.20.3-beta (45:45) Notable code and documentation changes ● Bitcoin Core #35493 (48:10) ● Core Lightning #9150 (50:57) ● BIPs #2248 (54:13) ● BIPs #2225 (56:07) ● Eclair #3346 (58:50) ● Eclair #3341 (1:02:22) ● LND #11019 (1:05:18) ● LND #11023 (1:09:03) ● Libsecp256k1 #1904 (1:11:49) ● HWI #839 (1:13:58)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Conduition, Ram, and Fabian Jahr to discuss Newsletter #417 . News ● Draft BIP for stale tip relay (29:26) Changing consensus ● CISA for taproot keypath spends (BIP460) (40:38) ● Segwit commitment to post-quantum witness data (57:51) ● PQC output type discussion (1:45) ● Input-triggered transaction expiry (1:03:36) ● Layered quantum recovery of hashed addresses (21:53) ● Segregated Data (SegData) BIP draft (1:08:33) Releases and release candidates ● Libsecp256k1 0.8.0 (1:15:24) Notable code and documentation changes ● Bitcoin Core #35501 (1:18:10) ● Core Lightning #9298 (1:22:47) ● Core Lightning #9353 (1:25:02) ● Eclair #3336 (1:26:15) ● LND #10942 (1:27:53) ● LND #10992 (1:29:35) ● Rust Bitcoin #6364 (1:31:55) ● Rust Bitcoin #6642 (1:33:22) ● BTCPay Server #7491 (1:36:52) ● BTCPay Server #7488 (1:38:35)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Rob Hamilton, PortlandHODL, Chandra Pratap, and fabohax to discuss Newsletter #416 . Action items ● Move funds secured by COLDCARD-generated keys (1:07) News ● Wallets generated by COLDCARD at risk of theft (2:18) ● Disclosure of two DoS vulnerabilities in Core Lightning (36:26) ● Proof of concept for a zero-knowledge proof of reserves (49:54) Selected Q&A from Bitcoin Stack Exchange ● What is Bitcoin's objective definition of transaction neutrality? (1:03:07) ● Why does BIP110's decentralization benefit not outweigh its impact on transaction neutrality? (1:05:17) ● Why does BIP110 require a 55% signaling threshold if its nodes reject non-signaling blocks? (1:09:46) ● Why use ElligatorSwift encoding in BIP324? (1:17:12) ● Was the OP_SUCCESSx reservation in BIP342 designed with specific opcode families in mind? (1:25:36) ● What is the difference between the long-term feerate and the discard feerate? (1:29:14) ● What is the quickest method for migrating a legacy wallet to a descriptor wallet on a pruned node? (1:32:40) ● Is there historical data on orphan/stale block rates during high-fee periods? (1:36:09) Releases and release candidates ● BTCPay Server 2.4.1 (1:41:25) ● Eclair 0.14.1 (1:42:14) Notable code and documentation changes ● Bitcoin Core #34628 (1:44:26) ● Bitcoin Core #28463 (1:49:49) ● Bitcoin Core #32800 (1:54:18) ● Bitcoin Core #34683 (1:56:54) ● Bitcoin Core #33014 (1:58:09) ● Eclair #3325 (1:59:31) ● BOLTs #1346 (2:00:57) ● BOLTs #1344 (2:01:01) ● BOLTs #1343 (2:04:14)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Fabian Jahr, Kruw, and Mojo to discuss ⁠Newsletter #415⁠ . News ● Draft BIP for full aggregation of BIP340 signatures (1:32) Changes to services and client software ● Wasabi Wallet 2.8.0 released (33:11) ● Coinswap v0.2.2 released (46:08) ● Go secp256k1 library announced (1:08:38) ● ASMap dashboard announced (21:06) ● Wavelength alpha released (1:10:01) Releases and release candidates ● Core Lightning v26.06.6 (1:13:06) ● Bitcoin Inquisition 29.4 (1:16:03) Notable code and documentation changes ● Bitcoin Core #35215 (1:17:11) ● Bitcoin Core #35766 (1:21:16) ● BIPs #2075 (1:22:44) ● BIPs #2204 (1:25:46) ● Core Lightning #8935 (1:28:43) ● Core Lightning #9324 (1:33:14) ● libsecp256k1 #1765 (1:35:16) ● Rust Bitcoin #6317 (1:41:46) ● BTCPay Server #7457 (1:44:10) ● BLIPs #71 (1:46:24)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Keagan McClelland and Andrew Toth to discuss Newsletter #414 . News ● Formal verification of the Bitcoin protocol (1:11) Releases and release candidates ● Bitcoin Core 30.3 (39:42) ● Bitcoin Core 29.4 (39:43) Notable code and documentation changes ● Bitcoin Core #35295 (52:43) ● Bitcoin Core #34897 (1:13:54) ● Bitcoin Core #35406 (1:16:13) ● Bitcoin Core #35380 (1:21:36) ● Bitcoin Core #35568 (1:07:36) ● Bitcoin Core #34538 (1:23:43) ● BIPs #2208 (1:25:52) ● LND #10962 (1:27:27) ● LND #10897 (1:30:12) ● BINANAs #21 (1:31:34)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Sjors Provoost to discuss Newsletter #413 . News ● Using fountain codes for IBD (13:53) Releases and release candidates ● Bitcoin Core 31.1 (22:52) ● LND v0.20.2-beta (28:49) Notable code and documentation changes ● Bitcoin Core #32489 (31:11) ● Bitcoin Core #32606 (33:59) ● Bitcoin Core #34020 (0:48) ● Core Lightning #9104 (42:55) ● Eclair #3323 (45:11) ● LND #10832 (46:24)

Mark “Murch” Erhardt and Mike Schmidt are joined by Conduition and Jeremy Rubin to discuss Newsletter #412 . Changing consensus ● Benchmarking SLH-DSA STARK aggregation (1:05) ● Bird of Prey 2 (BoP-2) non-malleable schnorr and PQ signatures (10:21) ● Lattice-based signatures (19:41) ● Public key recovery for P2MR EC leaves (25:50) ● Aligning privacy incentives in P2MR (30:48) ● Prohibit merkle internal node preimages that encode minimal 64-byte transactions (49:38) ● Triggering EC disabling with a NUMS point spend or hashrate majority (37:36) Releases and release candidates ● Bitcoin Core 31.1rc1 (1:32:43) ● Bitcoin Core 30.3rc1 (1:32:48) ● Bitcoin Core 29.4rc1 (1:32:52) ● Core Lightning v26.06.2 (1:36:01) ● LND v0.20.2-beta.rc1 (1:36:39) ● LND v0.21.1-beta (1:38:10) ● LDK v0.2.4 (1:38:57) Notable code and documentation changes ● Bitcoin Core #35266 (1:40:00) ● Bitcoin Core #35550 (1:41:10) ● Bitcoin Core #35610 (1:42:15) ● BIPs #2196 (1:43:52) ● BIPs #2165 (1:47:46) ● BIPs #2201 (1:50:13) ● LND #10900 (1:51:20) ● LND #10927 (1:52:37) ● LDK #4748 (1:54:13)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Nishant Bansal and Matthew Zipkin to discuss Newsletter #411 . News ● LND zero-timestamp gossip DoS disclosure (1:00) Selected Q&A from Bitcoin Stack Exchange ● Is it a bug that `OP_IF` is part of the tapscript opcodes? (34:02) ● Why would forbidding `OP_IF` in tapscript be a problem? (41:11) ● Does a softfork always succeed? (49:17) ● How to set up Bitcoin Core to mine a valid block after the BIP110 activation in August 2026? (56:44) ● Are BIP110 blocks on a branch with lower difficulty valid? (59:47) ● What is the story behind Bitcoin test networks? (1:07:41) ● Why was `-datacarriersize` redefined in 2022, and why was the 2023 proposal to expand it not merged? (1:15:35) ● Are chains of 26 unconfirmed transactions prohibited by the wallet in Bitcoin Core 31.0? (1:25:33) ● Are there changes in Bitcoin Core 29.0 that affect memory usage? (1:28:20) ● What is Bitcoin Core's release schedule? (1:30:21) Releases and release candidates ● LDK v0.1.10 (1:34:50) ● LDK v0.2.3 (1:35:31) ● BTCPay Server 2.4.0 (1:37:04) Notable code and documentation changes ● Bitcoin Core #35070 (1:39:27) ● Bitcoin Core #35182 (13:15) ● BIPs #2198 (1:46:09) ● LDK #4713 (1:51:17) ● LDK #4684 (1:53:47)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by rkrux, Roland Bewick, and Steven Roose to discuss ⁠Newsletter #410⁠ . News ● Discussion of removing RBF signaling from wallet transactions (0:57) Changes to services and client software ● Sparrow Wallet 2.5.0 adds silent payments receiving (59:55) ● Bark live on Bitcoin mainnet (29:46) ● Arké Ark wallet announced (32:18) ● Noah Ark wallet announced (31:52) ● Alby Hub v1.23.0 released (15:00) ● JoinMarket NG 0.32.0 released (1:01:02) Notable code and documentation changes ● Bitcoin Core #35221 (1:02:13) ● Bitcoin Core #35254 (1:06:59) ● Bitcoin Core #35498 (1:09:26) ● Eclair #3318 (1:11:06) ● LND #10789 (1:13:05) ● Rust Bitcoin #6321 (1:14:09) ● LDK #4685 (1:16:14)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Vasil Dimov to discuss Newsletter #409 . News ● Draft BIP for testnet5 (0:31) Releases and release candidates ● LND 0.21.0-beta (17:25) ● Core Lightning 26.06.1 (20:19) Notable code and documentation changes ● Bitcoin Core #35410 (21:28) ● Bitcoin Core #34779 (38:00) ● Bitcoin Core #32150 (41:36) ● LDK #4647 (45:14) ● BTCPay Server #7218 (51:34) ● BIPs #2186 (53:07)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Pyth and Ademan to discuss Newsletter #408 . News ● A post-quantum path for BIP324 (37:15) ● Discussion of QR signing payloads for miniscript wallets (1:27) Changing consensus ● CTV-only vault proof of concept (13:08) ● Post-quantum Lightning discussion (43:41) ● Quantum attack game theory (47:24) ● BIP54 64-byte transactions and potential legitimate uses (49:15) Releases and release candidates ● Core Lightning 26.06 (1:11:15) Notable code and documentation changes ● Bitcoin Core #35269 (1:15:42) ● Bitcoin Core #34644 (1:20:45) ● Bitcoin Core #34198 (1:22:21) ● LND #10813 (1:26:32) ● Rust Bitcoin #6250 (1:28:05) ● BOLTs #1338 (1:36:06) ● BOLTs #1326 (1:37:23)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Chandra Pratap to discuss Newsletter #407 . News ● Core Lightning assertion DoS disclosure (0:47) ● Bitcoin Core developer meeting transcripts (14:34) Releases and release candidates ● Eclair v0.14.0 (20:30) ● Core Lightning 26.06rc2 (23:01) Notable code and documentation changes ● Bitcoin Core #33966 (24:14) ● Bitcoin Core #34917 (28:04) ● Bitcoin Core #35017 (30:52) ● BIPs #1944 (35:25) ● BIPs #2108 (36:14) ● Eclair #3192 (39:28) ● LDK #4584 (40:28) ● LDK #4628 (41:27) ● LND #10552 (43:35) ● LND #10820 (48:52)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Oliver Gugger and 0xB10C to discuss Newsletter #406 . News ● Significant updates to BIP322 Generic Signed Message Format (1:17) ● TCP hole punching for Bitcoin nodes behind NATs (17:39) Changes to services and client software ● Ibis Wallet announced (40:15) ● LDK Server announced (41:10) ● Mempool.space v3.3.0 released (42:06) ● peer-observer P2P monitoring tooling (32:28) Notable code and documentation changes ● Bitcoin Core #29136 (43:27) ● Bitcoin Core #34893 (47:24) ● Bitcoin Core #34860 (48:20) ● Bitcoin Core #31298 (53:52) ● Bitcoin Core #28802 (57:04) ● Eclair #3298 (58:52) ● LDK #4575 (1:02:08) ● LND #10814 (1:03:13) ● Rust Bitcoin #6191 (1:04:35) ● BLIPs #42 (1:06:20)

Mark “Murch” Erhardt and Mike Schmidt are joined by Fabian Jahr to discuss ⁠Newsletter #405⁠ . News ● Bitcoin Core script interpreter remote crash disclosure (22:00) ● BIP proposal for UTXO set sharing over P2P network (0:42) Releases and release candidates ● Core Lightning 26.06rc1 (34:58) Notable code and documentation changes ● Bitcoin Core #35209 (36:44) ● BIPs #2116 (38:20) ● BIPs #2141 (44:13) ● Core Lightning #9116 (48:35) ● Core Lightning #9110 (50:27) ● LDK #4598 (52:10) ● LDK #4528 (53:30) ● LND #10612 (54:37) ● BTCPay Server #7354 (57:12) ● BDK #2195 (58:10) ● Bitcoin Inquisition #100 (1:00:00) ● BINANAs #20 (1:02:42)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Daniela Brozzoni, Naiyoma, and Thomas Voegtlin to discuss Newsletter #404 . News ● Possible solutions to node fingerprinting (1:14) ● Public fraud proof for just-in-time channels (19:21) Notable code and documentation changes ● Bitcoin Core #33796 (37:11) ● Bitcoin Core #21283 (39:30) ● BIPs #2150 (45:30) ● Eclair #3144 (52:30) ● Eclair #2887 (54:00) ● LDK #4592 (55:27) ● LND #9153 (56:52) ● Rust Bitcoin #5835 (58:02) ● BOLTs #995 (58:56) ● BOLTs #1228 (1:01:40) ● BOLTs #1327 (1:03:28)

Gustavo Flores Echaiz and Brandon Black are joined by Olaoluwa Osuntokun to discuss Newsletter #403 . News ● Binary fuse filters as an alternative to BIP158's GCS (19:05) Changing consensus ● Post-quantum HD wallets with fallback SPHINCS keys (31:07) ● Discussion of a post-quantum output type (34:42) ● Proposal to embed post-quantum keys in tapscript without consensus changes (38:03) ● BIP54 demonstration of slow blocks on signet (43:28) ● Post-quantum BIP86 recovery using zk-STARK proofs of BIP32 seeds (1:05) Releases and release candidates ● Core Lightning 26.04.1 (48:16) ● BTCPay Server 2.3.8 (50:15) ● BTCPay Server 2.3.9 (51:52) Notable code and documentation changes ● Bitcoin Core #33671 (52:39) ● Bitcoin Core #34885 (58:01) ● Bitcoin Core #33920 (59:57) ● Bitcoin Core #34911 (1:02:00) ● BIPs #1548 (1:04:47) ● HWI #831 (1:08:17) ● BDK #2188 (1:09:11) ● BDK #2115 (1:10:14)

Mark “Murch” Erhardt and Gustavo Flores Echaiz are joined by Toby Sharp to discuss Newsletter #402 . News ● Hornet Node's declarative executable specification of Bitcoin consensus rules (1:02) ● Onion message jamming in the Lightning Network (23:22) Selected Q&A from Bitcoin Stack Exchange ● Why did BIP342 replace CHECKMULTISIG with a new opcode, instead of just removing FindAndDelete from it? (40:58) ● Does SIGHASH_ANYPREVOUT commit to the tapleaf hash or the full taproot merkle path? (43:28) ● What does the BIP86 tweak guarantee in a MuSig2 Lightning channel, beyond address format? (45:23) Releases and release candidates ● Bitcoin Core 31.0 (47:10) ● Core Lightning 26.04 (54:26) ● LND 0.21.0-beta.rc1 (56:35) Notable code and documentation changes ● Bitcoin Core #33477 (57:55) ● Bitcoin Core #35006 (1:02:21) ● BIPs #1895 (1:04:31) ● BIPs #2142 (1:12:47) ● LDK #4555 (1:14:28) ● LND #10713 (1:16:23) ● LND #10754 (1:18:14)

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt are joined by Remix7531 and Luis Schwab to discuss Newsletter #401 . News ● Discussion of using nested MuSig2 in the Lightning Network (34:05) ● Formal verification of secp256k1 modular scalar multiplication (01:10) Changes to services and client software ● Coldcard 6.5.0 adds MuSig2 and miniscript (40:56) ● Frigate 1.4.0 released (41:46) ● Bitcoin Backbone updates (47:10) ● Utreexod 0.5 released (16:18) ● Floresta 0.9.0 released (19:41) Releases and release candidates ● Bitcoin Core 31.0rc4 (48:01) ● Core Lightning 26.04rc3 (49:00) Notable code and documentation changes ● Bitcoin Core #34401 (50:01) ● Bitcoin Core #35032 (51:51) ● Core Lightning #9021 (55:33) ● Core Lightning #9046 (56:53) ● LDK #4515 (58:25) ● LDK #4558 (59:51) ● LND #9985 (1:01:53) ● BTCPay Server #7250 (1:04:07) ● BIPs #2089 (1:07:28)