Bitcoin Core OP RETURN and spam explained by a Core Dev with Antoine Poinsot | SLP661

Bitcoin Core OP RETURN and spam explained by a Core Dev with Antoine Poinsot | SLP661

Stephan and Antoine discuss the complexities surrounding Bitcoin's OP_RETURN functionality and the ongoing debate about spam filtering on the Bitcoin network. They explore the implications of consensus rules, standardness, and the historical context of these discussions.

Antoine provides insights into the motivations behind changes in Bitcoin Core's policies and the potential future of Bitcoin as both a currency and a data storage solution. The conversation highlights the urgency of addressing OP_RETURN issues while also considering the broader implications of spam filtering and its impact on Bitcoin's usability and miner centralization.

The conversation also touches upon the growth of the UTXO set, the challenges of managing spam, and the philosophical differences between Bitcoin Core and alternative implementations.

Takeaways

🔸Bitcoin is defined by its consensus rules.

🔸There are tighter rules for unconfirmed transactions in Bitcoin Core.

🔸Standardness rules help prevent harmful transactions from being relayed.

🔸The OP_RETURN output was standardized to mitigate negative externalities.

🔸Historical context shows little demand for non-standard transactions.

🔸The urgency to fix OP_RETURN issues is debated among developers.

🔸Filters can work in certain contexts but not universally.

🔸Concerns about miner centralization are significant for Bitcoin's future.

🔸Speculating on motivations can detract from logical arguments.

🔸The future of Bitcoin Core depends on adapting to user demand. Miners are incentivized to include all transactions, including spam.

🔸Economic demand drives the use of alternative relay networks.

🔸Filtering transactions may not effectively stop spam propagation.

🔸The UTXO set growth is influenced by various factors, including spam.

🔸Changing Bitcoin's consensus rules can have unintended consequences.

🔸The cat and mouse game of filtering may lead to centralization risks.

🔸Communication between developers and users is crucial for consensus.

🔸The future of OP_RETURN is uncertain and requires community engagement.

🔸Inscriptions and meta-protocols complicate the UTXO set issue.

🔸Bitcoin's core philosophy resists changes that could limit its flexibility.

Timestamps:

(00:00) - Intro

(01:42) - Understanding Consensus & Relay policies in Bitcoin

(05:21) - Historical context of standardness Rules in Bitcoin Core

(11:05) - Are Bitcoin Core proponents being paid to ‘break’ Bitcoin?

(13:42) - Differentiating b/w OP_RETURN PR & the general spam filtering debate

(18:34) - Sponsors

(22:46) - Is Bitcoin Money or a Data Storage protocol? How do most Core devs view it?

(25:36) - Why not raise the OP_RETURN limit to ~150 bytes?

(29:02) - How urgent is it to fix the issue?

(31:56) - Why not let the node runners choose what they want to relay?

(39:03) - Do filters work or do they not?

(43:27) - Are concerns about UTXO bloat, miner centralisation, block propagation etc. being overplayed by Core devs?

(46:40) - Sponsors

(50:30) - Will miners who mine spam be penalised if node runners run knots?

(1:00:28) - Is Bitcoin Core serious about stopping UTXO bloat?

(1:07:00) - Why did Core not try to stop bare multisig spam?

(1:08:58) - Should Bitcoin devs be playing a whackamole game with spammers?

(1:18:24) - Summary & Future of OP_RETURN and spam concerns

Links:

Sponsors:

Stephan Livera links:

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