# Implementation **URL:** https://delvingbitcoin.org/c/implementation/8.md [Latest](https://delvingbitcoin.org/latest.md) · [Categories](https://delvingbitcoin.org/categories.md) · [Tags](https://delvingbitcoin.org/tags.md) --- ## [About the Implementation category](https://delvingbitcoin.org/t/about-the-implementation-category/16)
**Author:** [@admin](https://delvingbitcoin.org/u/admin)\ **Replies:** 0
For discussion of (practical) implementation techniques, either for particular Bitcoin software, or that may be relevant to many implementations. For example, how to minimise on-chain fees, or how to applying fuzz testi… --- ## [CLN: Self-Referential Channel Announcement DoS disclosure](https://delvingbitcoin.org/t/cln-self-referential-channel-announcement-dos-disclosure/2974)
**Author:** [@NishantBansal2003](https://delvingbitcoin.org/u/NishantBansal2003)\ **Replies:** 0\ **Last updated:** [October 24, 2026, 6:37am UTC](https://delvingbitcoin.org/t/cln-self-referential-channel-announcement-dos-disclosure/2974 "2026-10-24T06:37:23Z")
The issue discussed below was originally disclosed at nishantbansal2003.github.io and is reproduced here for discussion. Core Lightning v25.02 through v26.04 crash on a channel\_announcement whose node\_id\_1 and node\_id… --- ## [Several projects to make merchant adoption easier and cheaper](https://delvingbitcoin.org/t/several-projects-to-make-merchant-adoption-easier-and-cheaper/2967)
**Author:** [@andrewclicks](https://delvingbitcoin.org/u/andrewclicks)\ **Replies:** 2\ **Last updated:** [October 22, 2026, 9:42pm UTC](https://delvingbitcoin.org/t/several-projects-to-make-merchant-adoption-easier-and-cheaper/2967 "2026-10-22T21:42:24Z")
I would like to share with you several projects I have been working on over the past 2 years to make it easier to onboard merchants, particularly to lightning. Everybody knows there is a lot of rough UX around lightning … --- ## [Cost-Bounded Transaction Filtering Language](https://delvingbitcoin.org/t/cost-bounded-transaction-filtering-language/2966)
**Author:** [@bkeroack](https://delvingbitcoin.org/u/bkeroack)\ **Replies:** 1\ **Last updated:** [October 22, 2026, 2:07pm UTC](https://delvingbitcoin.org/t/cost-bounded-transaction-filtering-language/2966 "2026-10-22T14:07:25Z")
I designed a transaction filtering policy DSL and implemented it in satd, a full Bitcoin node implementation in Rust. This allows node runners to decide the exact transaction shapes they want their nodes to relay or incl… --- ## [Softfork before GTA VI?](https://delvingbitcoin.org/t/softfork-before-gta-vi/2913)
**Author:** [@cmp\_ancp](https://delvingbitcoin.org/u/cmp_ancp)\ **Replies:** 3\ **Last updated:** [October 22, 2026, 3:29am UTC](https://delvingbitcoin.org/t/softfork-before-gta-vi/2913 "2026-10-22T03:29:26Z")
Hi all Something that really bothered me is the sudden loss of momentum we had for pushing a new softfork for bitcoin. Some years ago the covenants topic was really hot, the entire community was pushing towards a consen… --- ## [Evaluating Deterministic BFT Finality within a Confidential UTXO State Machine](https://delvingbitcoin.org/t/evaluating-deterministic-bft-finality-within-a-confidential-utxo-state-machine/2965)
**Author:** [@finalis-core](https://delvingbitcoin.org/u/finalis-core)\ **Replies:** 0\ **Last updated:** [October 20, 2026, 8:16pm UTC](https://delvingbitcoin.org/t/evaluating-deterministic-bft-finality-within-a-confidential-utxo-state-machine/2965 "2026-10-20T20:16:07Z")
Hello everyone, I would like to share the architectural layout of an open-source, from-scratch C++ Layer-1 protocol called FinalisCore and open a technical discussion regarding its state transition model, specifically l… --- ## [Btc-verified October Update: Connecting Map to Territory](https://delvingbitcoin.org/t/btc-verified-october-update-connecting-map-to-territory/2964)
**Author:** [@ProofOfKeags](https://delvingbitcoin.org/u/ProofOfKeags)\ **Replies:** 0\ **Last updated:** [October 19, 2026, 4:32pm UTC](https://delvingbitcoin.org/t/btc-verified-october-update-connecting-map-to-territory/2964 "2026-10-19T16:32:15Z")
Originally published on my site. Replicating here because I think the Delving audience has an interest in this work. From the project’s inception until now, btc-verified has been focused on building up, layer by layer,… --- ## [Implicit Deletions and Improvements in Utreexo IBD](https://delvingbitcoin.org/t/implicit-deletions-and-improvements-in-utreexo-ibd/2881)
**Author:** [@Davidson](https://delvingbitcoin.org/u/Davidson)\ **Replies:** 3\ **Last updated:** [October 19, 2026, 7:46am UTC](https://delvingbitcoin.org/t/implicit-deletions-and-improvements-in-utreexo-ibd/2881 "2026-10-19T07:46:25Z")
Utreexo is a dynamic accumulator that allows the entire TXO set to be represented with only a couple of hashes. It does so by keeping the data structured as a forest of perfect Merkle trees, allowing nodes to keep only t… --- ## [SwiftSync -- Speeding up IBD with pre-generated hints (PoC)](https://delvingbitcoin.org/t/swiftsync-speeding-up-ibd-with-pre-generated-hints-poc/1562)
**Author:** [@theStack](https://delvingbitcoin.org/u/theStack)\ **Replies:** 18\ **Last updated:** [October 18, 2026, 3:10am UTC](https://delvingbitcoin.org/t/swiftsync-speeding-up-ibd-with-pre-generated-hints-poc/1562 "2026-10-18T03:10:03Z")
(EDIT: The working title for this thread was initially “IBD Booster”, but the official name for the proposal is now “SwiftSync”, see SwiftSync -- Speeding up IBD with pre-generated hints (PoC) - #2 by RubenSomsen and Swi… --- ## [Bitcoin-rs: an independent Bitcoin full node written in Rust](https://delvingbitcoin.org/t/bitcoin-rs-an-independent-bitcoin-full-node-written-in-rust/2918)
**Author:** [@gosunuts](https://delvingbitcoin.org/u/gosunuts)\ **Replies:** 2\ **Last updated:** [October 16, 2026, 10:00am UTC](https://delvingbitcoin.org/t/bitcoin-rs-an-independent-bitcoin-full-node-written-in-rust/2918 "2026-10-16T10:00:30Z")
I’d like to share early work on bitcoin-rs, an independent Bitcoin full node written in Rust. Like btcd, it’s an independent implementation, built to explore architectural and performance changes that are difficult to p… --- ## [Open-source Bitcoin multisig coordinator: shared signing queue, hardware wallets, live signet demo](https://delvingbitcoin.org/t/open-source-bitcoin-multisig-coordinator-shared-signing-queue-hardware-wallets-live-signet-demo/2957)
**Author:** [@tom2o17](https://delvingbitcoin.org/u/tom2o17)\ **Replies:** 1\ **Last updated:** [October 15, 2026, 1:41pm UTC](https://delvingbitcoin.org/t/open-source-bitcoin-multisig-coordinator-shared-signing-queue-hardware-wallets-live-signet-demo/2957 "2026-10-15T13:41:03Z")
I’ve open-sourced btc-safe, a self-hosted, watch-only Bitcoin multisig coordinator. One owner proposes a transaction. Every co-signer sees it in a shared queue and signs from their own device. It broadcasts once M of N h… --- ## [Bitcoin Core 32.0rc4 is now available](https://delvingbitcoin.org/t/bitcoin-core-32-0rc4-is-now-available/2958)
**Author:** [@fanquake](https://delvingbitcoin.org/u/fanquake)\ **Replies:** 0\ **Last updated:** [October 14, 2026, 6:17am UTC](https://delvingbitcoin.org/t/bitcoin-core-32-0rc4-is-now-available/2958 "2026-10-14T06:17:12Z")
Binaries for Bitcoin Core version v32.0rc4 are available from: Source code can be found under the signed tag This is a release candidate for a new major version release. Preliminary release notes for the release c… --- ## [Disclosure: DoS vulnerabilities fixed in Eclair v0.14.1](https://delvingbitcoin.org/t/disclosure-dos-vulnerabilities-fixed-in-eclair-v0-14-1/2928)
**Author:** [@erickcestari](https://delvingbitcoin.org/u/erickcestari)\ **Replies:** 2\ **Last updated:** [October 6, 2026, 1:08pm UTC](https://delvingbitcoin.org/t/disclosure-dos-vulnerabilities-fixed-in-eclair-v0-14-1/2928 "2026-10-06T13:08:36Z")
Two denial-of-service vulnerabilities in Eclair’s channel opening flow were fixed in Eclair v0.14.1. Users should upgrade to v0.14.1 or later to protect their nodes. LNF-2026-0003: open\_channel race DoS Eclair v0.14.0 a… --- ## [Descriptor syntax for hash preimages](https://delvingbitcoin.org/t/descriptor-syntax-for-hash-preimages/2935)
**Author:** [@jaonoctus](https://delvingbitcoin.org/u/jaonoctus)\ **Replies:** 0\ **Last updated:** [October 4, 2026, 8:45am UTC](https://delvingbitcoin.org/t/descriptor-syntax-for-hash-preimages/2935 "2026-10-04T08:45:03Z")
Summary Descriptors can carry private keys (pk(WIF/xprv)) and return them with listdescriptors private=true, but there is no equivalent for the secrets of miniscript hash fragments. I’d like to discuss adding a private f… --- ## [A simple backup scheme for wallet accounts](https://delvingbitcoin.org/t/a-simple-backup-scheme-for-wallet-accounts/1607)
**Author:** [@salvatoshi](https://delvingbitcoin.org/u/salvatoshi)\ **Replies:** 38\ **Last updated:** [October 1, 2026, 8:52am UTC](https://delvingbitcoin.org/t/a-simple-backup-scheme-for-wallet-accounts/1607 "2026-10-01T08:52:28Z")
For any wallet account that is not single-signature, backing up the descriptor is crucial, as its loss is likely to be catastrophic and lead to lost funds - even if the seeds that are in theory sufficient for recovery ar… --- ## [Where should wallets explain the differences between on-chain Bitcoin and Lightning?](https://delvingbitcoin.org/t/where-should-wallets-explain-the-differences-between-on-chain-bitcoin-and-lightning/2922)
**Author:** [@Anzus\_GemWallet](https://delvingbitcoin.org/u/Anzus_GemWallet)\ **Replies:** 0\ **Last updated:** [September 30, 2026, 2:48am UTC](https://delvingbitcoin.org/t/where-should-wallets-explain-the-differences-between-on-chain-bitcoin-and-lightning/2922 "2026-09-30T02:48:06Z")
I work in BD and support at Gem Wallet, rather than as a developer. One recurring usability issue I notice is that beginners often see on-chain Bitcoin and Lightning simply as “BTC,” without understanding that the paymen… --- ## [Bitcoin Core 32.0rc2 is now available](https://delvingbitcoin.org/t/bitcoin-core-32-0rc2-is-now-available/2921)
**Author:** [@fanquake](https://delvingbitcoin.org/u/fanquake)\ **Replies:** 0\ **Last updated:** [September 29, 2026, 1:14pm UTC](https://delvingbitcoin.org/t/bitcoin-core-32-0rc2-is-now-available/2921 "2026-09-29T13:14:27Z")
Binaries for Bitcoin Core version v32.0rc2 are available from: Source code can be found under the signed tag This is a release candidate for a new major version release. Preliminary release notes for the release c… --- ## [Disclosure: DoS vulnerabilities fixed in Eclair v0.14.0](https://delvingbitcoin.org/t/disclosure-dos-vulnerabilities-fixed-in-eclair-v0-14-0/2914)
**Author:** [@morehouse](https://delvingbitcoin.org/u/morehouse)\ **Replies:** 0\ **Last updated:** [September 24, 2026, 10:42pm UTC](https://delvingbitcoin.org/t/disclosure-dos-vulnerabilities-fixed-in-eclair-v0-14-0/2914 "2026-09-24T22:42:17Z")
Two denial-of-service vulnerabilities were fixed in Eclair v0.14.0. Users should upgrade to v0.14.0 or later to protect their nodes. LNF-2026-0001: Feature bit parsing DoS Eclair v0.13.1 and earlier parsed feature vect… --- ## [Silent Payments: Light Client Protocol](https://delvingbitcoin.org/t/silent-payments-light-client-protocol/891)
**Author:** [@setavenger](https://delvingbitcoin.org/u/setavenger)\ **Replies:** 16\ **Last updated:** [September 24, 2026, 10:07pm UTC](https://delvingbitcoin.org/t/silent-payments-light-client-protocol/891 "2026-09-24T22:07:41Z")
During the development of a couple light clients I jotted down some notes and created a very early draft for a Light Client Specification. The appendix of the SP BIP was used as a basis for this. The specification was de… --- ## [Unspendable keys in descriptors](https://delvingbitcoin.org/t/unspendable-keys-in-descriptors/304)
**Author:** [@salvatoshi](https://delvingbitcoin.org/u/salvatoshi)\ **Replies:** 30\ **Last updated:** [September 9, 2026, 6:29pm UTC](https://delvingbitcoin.org/t/unspendable-keys-in-descriptors/304 "2026-09-09T18:29:35Z")
With miniscript on taproot in core, and support coming soon in hardware signers, we will start seeing wallets exploring the new possibilities. One thing that will probably be useful for certain use cases and that doesn’… --- ## [Faster txid hash tables with SipHash-1-3-UJ](https://delvingbitcoin.org/t/faster-txid-hash-tables-with-siphash-1-3-uj/2834)
**Author:** [@sipa](https://delvingbitcoin.org/u/sipa)\ **Replies:** 2\ **Last updated:** [August 28, 2026, 5:46am UTC](https://delvingbitcoin.org/t/faster-txid-hash-tables-with-siphash-1-3-uj/2834 "2026-08-28T05:46:54Z")
I’d like to briefly highlight a small improvement that is coming in Bitcoin Core 32.0 (to be released in october): a custom variant of SipHash: SipHash-1-3-UJ. For context, Bitcoin Core’s validation and P2P logic extens… --- ## [Disclosure: Crashing CLN with a flood of pings](https://delvingbitcoin.org/t/disclosure-crashing-cln-with-a-flood-of-pings/2846)
**Author:** [@erickcestari](https://delvingbitcoin.org/u/erickcestari)\ **Replies:** 0\ **Last updated:** [August 27, 2026, 7:02pm UTC](https://delvingbitcoin.org/t/disclosure-crashing-cln-with-a-flood-of-pings/2846 "2026-08-27T19:02:56Z")
The following disclosure is copied verbatim from a blog post on erickcestari.dev, reproduced here to facilitate discussion. I found a critical DoS vulnerability in Core Lightning (CLN) while writing my own BOLT8 impleme… --- ## [Mempool.bitmixlist.org - the community mempool.space node](https://delvingbitcoin.org/t/mempool-bitmixlist-org-the-community-mempool-space-node/2836)
**Author:** [@Zenul\_Abidin](https://delvingbitcoin.org/u/Zenul_Abidin)\ **Replies:** 1\ **Last updated:** [August 27, 2026, 2:32pm UTC](https://delvingbitcoin.org/t/mempool-bitmixlist-org-the-community-mempool-space-node/2836 "2026-08-27T14:32:52Z")
I’m now running a production mirror of mempool.space. This particular mirror is based on v3.3.1 \[9332d9db\], and only branding changes have been made. Otherwise, it’s identical to the main site. It is based on mempool… --- ## [Covenants.diy: a node editor for covenant scripts](https://delvingbitcoin.org/t/covenants-diy-a-node-editor-for-covenant-scripts/2826)
**Author:** [@askii21m](https://delvingbitcoin.org/u/askii21m)\ **Replies:** 2\ **Last updated:** [August 26, 2026, 12:02pm UTC](https://delvingbitcoin.org/t/covenants-diy-a-node-editor-for-covenant-scripts/2826 "2026-08-26T12:02:49Z")
I’m working on an open-source node editor for experimenting with covenant scripts. covenants.diy You can wire nodes together and it builds the taproot output, assembles the tapscript, computes the sighash, and runs the… --- ## [Seedroller and keyderiver: cli tools to generate BIP39 seed words and derive BIP380 keys](https://delvingbitcoin.org/t/seedroller-and-keyderiver-cli-tools-to-generate-bip39-seed-words-and-derive-bip380-keys/2822)
**Author:** [@bubb1es](https://delvingbitcoin.org/u/bubb1es)\ **Replies:** 2\ **Last updated:** [August 24, 2026, 2:39pm UTC](https://delvingbitcoin.org/t/seedroller-and-keyderiver-cli-tools-to-generate-bip39-seed-words-and-derive-bip380-keys/2822 "2026-08-24T14:39:27Z")
In light of recent events I became interested in how to safely generate a strong random seed. The closest tool I found in rust is seedtool-cli-rust but it has a lot of dependencies I don’t recognize and I prefer building… --- ## [Generate truly random seed words using only dice or playing cards](https://delvingbitcoin.org/t/generate-truly-random-seed-words-using-only-dice-or-playing-cards/2814)
**Author:** [@seed-cat](https://delvingbitcoin.org/u/seed-cat)\ **Replies:** 2\ **Last updated:** [August 18, 2026, 3:11pm UTC](https://delvingbitcoin.org/t/generate-truly-random-seed-words-using-only-dice-or-playing-cards/2814 "2026-08-18T15:11:33Z")
In light of the ColdCard incident, I have created a system that allows anyone to easily generate their seed words using only ordinary dice or playing cards. Each seed word requires only 3 rolls of two dice or dealing 3 … --- ## [Towards New Self-Custody Best Practices](https://delvingbitcoin.org/t/towards-new-self-custody-best-practices/2768)
**Author:** [@seed-cat](https://delvingbitcoin.org/u/seed-cat)\ **Replies:** 5\ **Last updated:** [August 18, 2026, 7:46am UTC](https://delvingbitcoin.org/t/towards-new-self-custody-best-practices/2768 "2026-08-18T07:46:31Z")
Self-Custody Best Practices By now, many Bitcoiners are aware of the risk of trusting a single wallet vendor with their life savings. The low-entropy vulnerability in the Coldcard has resulted in over $100M in losses, w… --- ## [Deterministic UTXO consolidation under volatile fee regimes](https://delvingbitcoin.org/t/deterministic-utxo-consolidation-under-volatile-fee-regimes/2257)
**Author:** [@babyblueviper1](https://delvingbitcoin.org/u/babyblueviper1)\ **Replies:** 4\ **Last updated:** [August 17, 2026, 3:48pm UTC](https://delvingbitcoin.org/t/deterministic-utxo-consolidation-under-volatile-fee-regimes/2257 "2026-08-17T15:48:29Z")
Hi all, I’ve been thinking about UTXO consolidation not purely as a fee optimization problem, but as a potential determinism and correctness surface in wallet transaction construction. Specifically, I’m interested in c… --- ## [Running Core's real consensus code inside a zkVM](https://delvingbitcoin.org/t/running-cores-real-consensus-code-inside-a-zkvm/2811)
**Author:** [@defenwycke](https://delvingbitcoin.org/u/defenwycke)\ **Replies:** 9\ **Last updated:** [August 17, 2026, 7:10am UTC](https://delvingbitcoin.org/t/running-cores-real-consensus-code-inside-a-zkvm/2811 "2026-08-17T07:10:43Z")
Proving Bitcoin Running Core’s real consensus code inside a zkVM. Full block validity proofs generated from unmodified Bitcoin Core. TL;DR I have compiled Bitcoin Core v28’s consensus code to riscv32im, run it inside a R… --- ## [Reducing Bitcoin Full Node Storage Without Consensus Changes](https://delvingbitcoin.org/t/reducing-bitcoin-full-node-storage-without-consensus-changes/2790)
**Author:** [@BrokenMachine](https://delvingbitcoin.org/u/BrokenMachine)\ **Replies:** 7\ **Last updated:** [August 15, 2026, 11:29am UTC](https://delvingbitcoin.org/t/reducing-bitcoin-full-node-storage-without-consensus-changes/2790 "2026-08-15T11:29:03Z")
I’ve been mulling over the blockchain size “problem” for a while now, particularly with an eye toward being able to continue running a full node comfortably well into the future. I wanted to see whether there was a usefu… [Next page](https://delvingbitcoin.org/c/implementation/8.md?page=1)