Bitcoin Socratic Seminar #49 - Topic Suggestions

[bolty-from-atl-bitlab]

Bitcoin Socratic Seminar #49

📅 Date: Wednesday, April 15, 2026
📍 Location: ATL BitLab

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Topic Suggestions

Post topic suggestions as comments below. Each comment should include:

• Topic title
• Link(s)
• Brief description

Approval: React with 🚀 to indicate interest. Topics approved by @sbddesign or @alexlwn123 will be added to the event page.

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Created by BOLTy via GitHub App 🤖

[bolty-from-atl-bitlab]

React Native Support Merged into Fedimint Web SDK — Alex Lewin on X — Fedimint's Web SDK now supports React Native, enabling mobile app developers to integrate Fedimint directly into cross-platform apps.

[bolty-from-atl-bitlab]

Bitcoin Core: coinbase_tx in getblock RPC — PR #34512 / Optech #394 — New coinbase_tx field at verbosity 1+ returns coinbase version, locktime, sequence, and witness without decoding all block txs; useful for BIP54 monitoring.

LDK: Collaborative Multipath Payments — PR #4373 / Optech #394 — Multiple wallets/nodes can now collaboratively pay a single invoice by each sending part of a multipath payment.

Eclair: Auto Channel Type Selection — PR #3250 / Optech #394 — OpenChannelInterceptor auto-selects channel_type for LSP-initiated channels; defaults to anchor, simple taproot channels expected next.

BDK: Transaction Output Tracking Methods — PR #2081 / Optech #394 — New spent_txouts() and created_txouts() methods for easy wallet transaction tracking.

[bolty-from-atl-bitlab]

V-PACK: Stateless VTXO Verification for Ark — Delving Bitcoin / Optech #395 — Proposed standard for independently verifying VTXOs across Ark implementations (Arkade, Bark), targeting embedded environments like hardware wallets.

TEMPLATEHASH-CSFS-IK Miniscript & PSBT Integration — bitcoin-dev / Optech #395 — Antoine Poinsot's preliminary work integrating OP_TEMPLATEHASH into miniscript and PSBTs, revealing challenges with Script's stack structure and argument ordering.

Algorithm Agility for Bitcoin — bitcoin-dev / Optech #395 — Ethan Heilman proposes a fallback signing algorithm in BIP360 P2MR scripts to bridge between cryptosystems if secp256k1 breaks; Pieter Wuille responds with fundamental limitations of supporting multiple signing schemes simultaneously.

BIP442: OP_PAIRCOMMIT Published — BIPs #1699 / Optech #395 — New tapscript opcode that hashes two stack elements together, providing multi-commitment like OP_CAT but without recursive covenants; part of LNHANCE soft fork proposal.

BIP352: Silent Payments K_max = 2323 Merged — BIPs #2106 / Optech #395 — Per-group recipient limit set to 2323 (matching max P2TR outputs in a standard tx), capping worst-case scanning time from adversarial transactions.

BIP128: Timelock Recovery Plans — BIPs #2068 / Optech #395 — Standard JSON format for storing pre-signed alert+recovery transactions with relative timelocks for wallet recovery if owner loses access.

[bolty-from-atl-bitlab]

LND #10604: SQL Backend for Payments — PR #10604 / Optech #395 — SQLite/Postgres backend for outgoing payments database, replacing bbolt KV store, with experimental migration path.

Bitcoin Core #34616: Cluster Linearization Cost Model — PR #34616 / Optech #395 — More accurate CPU time cost model for the spanning-forest cluster linearization algorithm, calibrated across diverse hardware.

BOLTs #1301: Higher Dust Limit for Anchor Channels — BOLTs #1301 / Optech #395 — Spec now recommends higher dust_limit_satoshis for anchor channels since zero-fee HTLC transactions can make outputs uneconomical to claim.

Bitcoin Core 28.4rc1 — Release / Optech #395 — Maintenance release candidate with wallet migration fixes and DNS seed removal.

[bolty-from-atl-bitlab]

Bitcoin Core #33616: Skip Ephemeral Dust Check During Reorgs — PR #33616 / Optech #395 — Confirmed transactions re-entering mempool during reorgs no longer rejected by ephemeral dust policy; follows same pattern as TRUC topology skip.

Eclair #3256: ChannelFundingCreated Event — PR #3256 / Optech #395 — New event emitted when funding/splice tx is signed, letting the non-funding side validate inputs and potentially force-close before confirmation.

Eclair #3258: Interactive Tx Validation Plugin — PR #3258 / Optech #395 — Plugin trait to inspect and reject remote peer inputs/outputs in dual-funded channel opens and splices before signing.

LDK #4402: Trampoline HTLC Claim Timer Fix — PR #4402 / Optech #395 — Fixes HTLC claim deadline to use actual CLTV expiry rather than onion payload value, avoiding unnecessarily tight deadlines for trampoline payments.

[bolty-from-atl-bitlab]

Eclair #3255: scid_alias Fix for Public Channels — PR #3255 / Optech #395 — Fixes auto channel type selection (#3250) to exclude scid_alias for public channels, as the BOLTs only allow it for private channels.

[bolty-from-atl-bitlab]

RootScope: Deterministic Reconstruction of Taproot Script-Path Commitments — Delving Bitcoin — Pure Python tool that reconstructs the full TapLeaf→TapBranch→TapTweak→output key commitment chain from a witness, exposing every intermediate value for inspection.

Q-Lock: Quantum-Resistant Spending via ECDSA + Hash-Based Secrets — bitcoin-dev — Proposed alternative to BIP-360 P2QRH: adds a hash-based secret layer on top of ECDSA using a two-phase commit-reveal scheme (~3 KB vs 24 KB Lamport), requiring a soft fork with 1-2 new opcodes.

[BIP Proposal] Peer Feature Negotiation (BIP434) — bitcoin-dev — AJ Towns responds to Antoine Riard's FEATURE message proposal for P2P feature negotiation with design feedback.

[bolty-from-atl-bitlab]

Draft BIP: 24-bit nVersion Nonce Space for Miners — bitcoin-dev / Optech #395 / PR #34779 — Matt Corallo proposes expanding miner nonce space in nVersion from 16 to 24 bits (superseding BIP320), with implementation already filed; simplifies ASIC design without distorting block timestamps.

Hourglass V2 Update — bitcoin-dev / Optech #395 — Mike Casey updates the Hourglass soft fork proposal to restrict P2PK-locked Bitcoin spending to 1 output and 1 BTC per block, mitigating potential market impact of quantum attacks on lost coins.

Writing Fuzz Targets for Wallets: Avoiding Known Issues — Delving Bitcoin — Bruno Garcia on practical strategies for writing effective wallet fuzz targets that avoid triggering known benign issues.

BIP54: Sequence and Timestamp for GBT — bitcoin-dev — Sjors Provoost updates BIP54 proposal, dropping the "version" field; adds sequence number and timestamp to getblocktemplate for mining pool coordination.

[bolty-from-atl-bitlab]

OP_TEMPLATEHASH-CSFS-IK Support in Miniscript and PSBTs — bitcoin-dev / Optech #395 — Antoine Poinsot's preliminary work integrating the taproot-native OP_TEMPLATEHASH soft fork proposal into miniscript and PSBTs, highlighting challenges with Script's stack structure requiring OP_SWAP before each OP_CHECKSIGFROMSTACK.

[bolty-from-atl-bitlab]

Algorithm Agility for Bitcoin — bitcoin-dev / Optech #395 — Ethan Heilman proposes adding a backup signing algorithm in BIP360 P2MR scripts as a fallback bridge between primary signing algorithms, so future breaks of either one need not be as high-stakes as the current quantum threat to secp256k1.

[bolty-from-atl-bitlab]

Limitations of Cryptographic Agility in Bitcoin — bitcoin-dev / Optech #395 — Pieter Wuille argues that because Bitcoin ownership is belief-based, competing signature schemes undermine the ownership invariant — old schemes will eventually need to be disabled during migration from one to another.

[bolty-from-atl-bitlab]

BIP 54 (Consensus Cleanup) Active on Bitcoin Inquisition — bitcoin-dev — BIP 54 now active on Inquisition since block 291168; fresh discussion today between Poinsot and Lopp on the tradeoffs of publicly demonstrating slow-but-not-worst-case blocks to build consensus support without leaking full attack optimization details.