Satoshi Scoop Weekly, 5 September 2025
🍨 Your weekly bite of the latest updates from the Bitcoin ecosystem!
Crypto Insights
Differential fuzzing tool bitcoinfuzz keeps uncovering protocol implementation bugs
bitcoinfuzz is a differential fuzzing tool for Bitcoin protocol implementations and libraries. Developer Bruno Garcia introduced the latest progress: after a refactor and following a modular approach similar to cryptofuzz, bitcoinfuzz now lets developers choose which project to fuzz and allows modules to be built individually.
So far, bitcoinfuzz has discovered and reported over 35 bugs across projects including btcd, rust-bitcoin, rust-miniscript, Embit, Bitcoin Core, Core Lightning, and LND.
New BIP proposal: Elliptic curve opcodes to unlock new possibilities for Bitcoin Script
Roasbeef proposed a new BIP draft to add fundamental elliptic curve opcodes to Bitcoin. One of their functions is to allow Bitcoin Script to compute the top-level Taproot output public key. This could enable new forms of on-chain state machines, as well as support other use cases.
New BIP proposal: Covenant-only Taproot outputs as a hidden security layer for institutional Bitcoin holdings
Monteagudo proposed a new BIP draft to introduce covenant-only Taproot outputs, a wallet-level security mechanism that is optional but irreversible. Once enabled, covenant-only mode disables key-path spending and enforces script-path spending, creating invisible transaction restrictions that only become visible if violated. This mechanism adds an optional layer of security for high-value institutional Bitcoin holdings, preventing unauthorized access while preserving transaction privacy until restrictions are triggered.
Glock: A new accountable optimistic Bitcoin smart contract design based on garbled circuits
Liam Eagen introduced a new mechanism called Glock, which uses garbled circuits to create auditable computational contracts for optimistic smart contract verification on Bitcoin. Similar to Delbrag, it uses garbled circuits to leak a secret and generate a signature as a fraud proof, and further proposes the first concretely practical construction that doesn’t require Grug. Like BitVM2 and Delbrag, Glock25 reduces the verification of arbitrary bounded computation to the verification of a SNARK. In Glock25, a designated verifier version of a modified SNARK Pari with smaller proof size is used. By combining Cut-and-Choose, Verifiable Secret Sharing (VSS), and Adaptor Signatures, Glock25 achieves security against malicious behavior. Compared to other Glock constructions (such as Groth16-based ones), this approach reduces communication, computation, and on-chain complexity.
He provides a detailed explanation of Glock in this paper.
Bitcoin inheritance solution Nunchuck adds Miniscript support
Miniscript (BIP-379) was introduced by Pieter Wuille and collaborators. As “a language for writing Bitcoin Scripts in a structured way, enabling analysis, composition, and generic signing”, it addresses usability and security issues of raw script while remaining fully compatible with current Bitcoin rules.
The Bitcoin inheritance solution Nunchuck recently announced support for Miniscript, enabling custom Bitcoin scripts to protect coins in more personalized ways. Here’s their 101 guide: Nunchuk Miniscript 101: A Technical Guide
The BTC ecosystem race: who will emerge as the ultimate value carrier?
This article summarizes and compares different Bitcoin L2 technology paths and their trade-offs, including: Lightning Network, Bitcoin Thunderbolt, Merge Mining, RGB and RGB++, ZK-Rollup, and BitVM. It highlights how each solution emphasizes different priorities in its design.
For example, the Lightning Network focuses on payment efficiency and has developed a mature node network for small payments and off-chain settlement. RGB and RGB++ emphasize asset security, leveraging client-side validation to ensure reliable asset states. ZK-Rollup approaches typically combine mature EVM implementations with modular security verification, offering strong composability and cross-chain scalability, making them especially suitable for DeFi and AI agent use cases. BitVM, in contrast, pursues ultimate nativeness—enabling smart contracts on Bitcoin without altering BTC consensus. Though still early, it represents a frontier experiment pushing Bitcoin’s computational boundaries.
The author argues that while it’s uncertain which solution will ultimately prevail, any long-term viable approach must meet three fundamental criteria: BTC-native compatibility, verifiable security, and strong support for upper-layer applications. Moreover, the trend of cross-stack integration is becoming increasingly apparent—for example, stablecoin integration within the Lightning Network, or combining ZK-Rollups with RGB.
Tether to issue USDT on RGB protocol
Tether announced plans to issue USDT on the RGB protocol, enabling native stablecoin issuance on top of Bitcoin.
According to the plan, USDT holders will be able to store and transfer both Tether stablecoins and Bitcoin within the same wallet, conduct private transactions without exposing on-chain balances or flows, and experience instant settlement via RGB’s Lightning-based transfers. Tether also plans to support offline transfers, broadening use cases in low-connectivity environments.
