Bitcoin Optech: Newsletter #390 Recap

Mark “Murch” Erhardt and Gustavo Flores Echaiz are joined by Liam Eagen to discuss Newsletter #390 (https://bitcoinops.org/en/newsletters/2026/01/30/).

News ● Argo: a garbled-circuits scheme with more efficient off-chain computation (0:48) ● LN-Symmetry update (26:05)

Selected Q&A from Bitcoin Stack Exchange ● What is stored in dbcache and with what priority? (34:21) ● Can one do a coinjoin in Shielded CSV? (24:02) ● In Bitcoin Core, how to use Tor for broadcasting new transactions only? (36:47) ● Brassard-Høyer-Tapp (BHT) algorithm and Bitcoin (BIP360) (38:31) ● Why does BitHash alternate sha256 and ripmed160? (39:24)

Releases and release candidates ● Libsecp256k1 0.7.1 (41:09)

Notable code and documentation changes ● Bitcoin Core #33822 (42:59) ● Bitcoin Core #34269 (44:50) ● Core Lightning #8850 (47:38) ● LDK #4349 (49:16) ● Rust Bitcoin #5470 (50:54) ● Rust Bitcoin #5443 (51:26) ● BDK #2037 (52:51) ● BIPs #2076 (55:49) ● BIPs #1500 (59:39)