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@ Cryptape
2025-05-23 01:12:10Crypto Insights
Introducing Generalized Program Composition and Coin Delegation into Bitcoin
Joshua Doman proposed a proof-of-concept called Graftleaf, aiming to achieve generalized program composition and delegation in Taproot in a simple and secure way. Graftleaf is a new Taproot leaf version (0xc2) that uses the annex to perform delegation. It adds two key features:
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Composition: The ability to sequentially execute zero, one, or multiple witness programs, including a locking script.
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Delegation: The ability to add additional spending conditions at signing time, which can include arbitrary combinations of programs and scripts.
This design overcomes the limitations of previous proposals by supporting complex script composition and delegation, promising backward compatibility, improved privacy and fungibility with the existing P2TR addresses.
Why OP_CHECKCONTRACTVERIFY (CCV) Will Replace OP_VAULT
A post mainly discusses the current status of Bitcoin script opcode OP_VAULT (BIP-345) and the possibility of it being replaced by OP_CHECKCONTRACTVERIFY (CCV, BIP-443). Key factors include:
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CCV is a more general version of OP_VAULT, inheriting some features such as amount modes and deferred (cross-input) checks.
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CCV supports replacing multiple script tapleaf nodes, has a simpler interface, and a lighter script interpreter implementation.
The author also points out CCV’s shortcomings and possible future extensions:
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Currently, there is a lack of supporting documentation and tools, and the BIP is not yet fully completed.
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A VAULT-decorator opcode may be needed to implement certain advanced features, such as requiring collateral lockup when unvaulting, or adding some rate-limiting behavior. These features are currently difficult to achieve.
Despite this, CCV remains a better foundation for building vault functionality.
Enabling Recursive Covenants via Self-Replication
Bram Cohen proposed adding a few simple opcodes to Bitcoin Script to enable recursive covenants in a natural and straightforward way. He illustrated with examples that a practical and useful script can be achieved through Quine, without other more complex tricks; developers writing recursive covenants must be aware of the importance of this approach.
UTXO Set Report from Mempool Research: Nearly Half of Bitcoin UTXOs Are Less Than 1,000 Sats
During the OP_RETURN debate in April-May 2025, the impact of inserting arbitrary data into transactions on the UTXO set sparked much discussion. In this report, Mempool studied the UTXO set, highlighting the fragmentation and bloat issues, especially due to small transactions and data embedding, which increase the storage and validation burden for node operators.
Key findings include:
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Severe Bloat: Currently, about 49% of UTXOs are less than 1,000 satoshis (about $1). Most of these use Taproot address format and may be related to data embedding schemes (like Ordinals) or related transfer mechanisms. Although these UTXOs can usually be spent, before they are, they increase the storage and validation burden for all node operators.
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Significant Proportion of Inscription-Related UTXOs: About 30% of UTXOs are related to inscription.
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Large Number of Long-Unspent UTXOs: There are over 100,000 old Counterparty UTXOs using Pay to Multisig (p2ms) scripts, which have existed for over 10 years. Although they make up a small proportion of the total (about 173 million UTXOs), they are a typical example of UTXO bloat.
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Taproot Becomes the Most Common UTXO Type: Among all UTXO types, Taproot (p2tr) has the highest proportion at 34.2%, followed by traditional p2pkh (28.8%) and p2wpkh (26.5%). However, in terms of total value stored, Taproot’s share is relatively low, indicating it is mainly used for small transactions or data embedding.
The report concludes by mentioning that as the UTXO sets continue to grow, Utreexo and SwiftSync are two scaling methods for maintaining Bitcoin’s accessibility to a wide range of node operators.
Visualization of Bitcoin Mainnet Data
mainnet-observer, built and maintained by developer @0xB10C, visualizes multiple data points from the Bitcoin mainnet, including:
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Mining a single block currently requires over ~500,000,000,000,000,000,000,000,000 (500 zeta or 5×10²³) hash attempts.
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Over 42 BTC are now permanently lost in provably unspendable OP_RETURN outputs.
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Daily updated “Mining Centralization Index” (with proxy pools)
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Bitcoin mining is currently highly centralized, with 6 pools producing and mining over 95% of block templates.
Path Queries: Addressing Payment Reliability and Routing Limitations
brh28 initiated a discussion on Lightning Network payment routing, focusing on issues like liquidity uncertainty and inefficient path discovery. He proposed a new path query mechanism—allowing nodes to dynamically share information through path queries, fostering a more decentralized routing ecosystem. This can improve the success rate of large payments and reduce reliance on a completely synced channel graph. Although there are still some privacy concerns, this method provides nodes with a controllable information disclosure mechanism and is expected to revolutionize current payment routing approaches.
Bitlayer and Sui Achieve Trust-Minimized BitVM Bridge
Bitlayer and Sui integrated the BitVM Bridge, launching Peg-BTC (YBTC)—bridging native Bitcoin to the Sui ecosystem via BitVM Bridge. BitVM Bridge is a trust-minimized bridge powered by Bitlayer and supported by the advanced BitVM smart contract framework.
Ark Protocol Litepaper
Ark recently released its litepaper: Ark: A UTXO-based Transaction Batching Protocol, outlining its technical foundation. As an innovative Bitcoin scaling protocol, Ark enables off-chain transaction execution while allowing users full control over their funds. This is achieved by introducing “virtual UTXOs” (VTXOs), allowing users to transact off-chain while retaining the ability to unilaterally exit to the Bitcoin main chain. Coordinated by an operator who batches user activities into on-chain commitments, Ark achieves high transaction throughput with minimal on-chain footprint. This provides Bitcoin with a simple and user-friendly scaling solution that offers a practical path for Layer 2 solutions that are inefficient or costly to execute on the main chain.
Top Reads on Blockchain and Beyond
List of Known Real-World Bitcoin Attack Incidents
Here is a list of real-world attacks against Bitcoin/crypto asset holders over the years.
The Internet Capital Market: Free Avenue for Developers, or Another Wave of FOMO?
This post discusses Internet Capital Markets (ICM)—decentralized platforms where funds flow directly to app builders and creators. ICM combines crowdfunding, token issuance, and equity speculation, eliminating the need for VCs, banks, or app stores. In 2025, more independent developers are issuing app tokens directly via X and tools like Believe and Launchcoin, attracting mass investment.
ICM Proponents argue this model breaks traditional funding barriers, making innovation more democratic and accessible; while critics warn that ICM is becoming a hotbed for hype and short-term speculation, with many projects lacking real products or long-term value. The author believes whether ICM can become the next milestone for Web3 hinges on whether it can break free from the cycle of “speculation becomes product traction” and deliver real user value and sustained innovation.
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