Research Forums · Tue, Nov 3, 2026

Research discussions on ethresear.ch and Delving Bitcoin.

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ethresear.ch

Storage-optimized replay protection: from hash => bool to packed flag lanes, and can the protocol offer better?

In briefStorage-optimized replay protection: packed flag lanes versus per-flag booleans, and whether the protocol could offer cheaper storage.

SummaryThe post covers protocols that must permanently record one small flag per event, such as privacy-pool nullifiers and unordered nonces. It compares three layouts: one boolean per flag, a 256-flag bitmap word, and per-party lanes within a word, with gas estimates for each. The author argues that packing can only approach fixed cost floors, and asks whether the execution layer could offer replay flags directly at a price suited to that use.

Delving Bitcoin

Full OP_RETURN value pruning

In briefFull OP_RETURN value pruning for satd Bitcoin nodes

SummaryThe satd Bitcoin node implementation adds an optional feature to prune OP_RETURN output values from on-disk block files using hole-punching. It is controlled by options such as -pruneopreturn, -pruneopreturnsize and -restoreopreturns. The author argues this lets operators express preferences without breaking consensus, but notes disk usage may increase rather than decrease and that pruned nodes cannot serve some block data.