SUNDAY, MAR08
1. Fuzzing BTC wallets, 2. Post-quantum sidechain, 3. Public miner selling, 4. Keonne and the skinwalker
Supported by Proto and Bitkey - part of the Bitcoin ecosystem at Block, Inc.
1. wallets
Bitcoin Core developer Bruno Garcia has published a detailed guide on writing effective fuzz targets for bitcoin wallets, addressing performance and determinism problems that plague stateful software testing. Writing on the Delving Bitcoin developer forum, Garcia explains that naive fuzzing of wallet code wastes millions of potential test executions on expensive but irrelevant operations like keypool refills, cryptographic routines, and disk I/O. The post details specific mitigations used in Bitcoin Core's own fuzz targets: reducing the keypool size to 1, mocking the fee estimator and database layer, constraining descriptor complexity to avoid "computationally pathological" inputs, and building a reusable wallet fixture that eliminates per-iteration setup costs. Garcia notes the guide was inspired by conversations with BDK maintainer Leo about similar challenges in that library's fuzzing efforts. A follow-up discussion touched on ensemble fuzzing, running AFL++, libfuzzer, and honggfuzz simultaneously against shared inputs to improve coverage. The work reflects a broader push to harden bitcoin wallet infrastructure through systematic automated testing, with techniques now transferable across the ecosystem's major wallet libraries.
-EDITOR·OP_DAILY2. post
Blockstream Research has deployed post-quantum signature verification on the Liquid Network in production, broadcasting what the company believes are the first transactions on a live Bitcoin sidechain secured with a post-quantum signature scheme. The implementation uses Simplicity, Blockstream's smart contract language, to run a complete cryptographic verifier without requiring any changes to Liquid's consensus rules. The underlying scheme is SHRINCS, a hash-based post-quantum signature standard developed internally and optimized for blockchain constraints, offering a stateful mode for compact everyday signatures and a stateless fallback to preserve fund access if a user loses signing state. Blockstream notes the deployment does not make Liquid fully quantum-resistant since the Bitcoin peg mechanism, Confidential Assets commitments, and the blocksigning protocol remain classically secured. Protection is strictly opt-in: users move funds into a Simplicity contract requiring post-quantum signatures to spend, with no wallet integration yet available. In a nod to the project's origins, Blockstream filled required transaction padding with the Bitcoin whitepaper rather than zeros. The verifier library is open source, and the company frames Liquid explicitly as a proving ground for techniques that could eventually inform quantum-resistance work on Bitcoin itself.
-EDITOR·OP_DAILY3. selling
Public bitcoin miners have shed roughly 15,096 BTC from peak collective holdings as capital rotates toward AI infrastructure buildouts, according to James Van Straten writing in CoinDesk. The selloff is concentrated among a handful of major operators: Core Scientific liquidated $175 million in bitcoin as its AI pivot accelerated, dropping from a high of 9,618 BTC to roughly 630 BTC, while Riot Platforms sold $200 million worth in the final two months of 2025 alone. Bitdeer and Bitfarms have reduced holdings to near zero, with Bitfarms CEO Ben Gagnon stating plainly, "We are no longer a Bitcoin company." The structural logic follows that mining margins that once reached 90% during the 2021 bull run have since collapsed under competitive hashrate, rising energy costs, and a bitcoin price sitting nearly 50% below its all-time high. Miners already operating data centers find AI compute hosting a more capital-efficient use of the same infrastructure. MARA Holdings remains the largest holder at 53,822 BTC but has softened its strict accumulation stance, with roughly 28% of holdings loaned or pledged. The trend suggests the HODL-as-corporate-strategy era among public miners is giving way to a more opportunistic treasury posture across the sector.
-EDITOR·OP_DAILY4. skinwalker
Samourai Wallet developer Keonne Rodriguez, serving a five-year federal sentence for building non-custodial bitcoin privacy software, continues documenting life inside FPC Morgantown in his fifth letter published by The Rage. Rodriguez describes securing a transfer from the facility's rowdy B-Wing dormitory to the quieter A-Wing after two months of working as a bathroom janitor to prove himself worthy of the move, a process requiring written requests the Bureau of Prisons calls "cop outs." He recounts the sleep deprivation, lack of personal autonomy, and grinding indignities of minimum-security incarceration with dark humor, noting that even minor confrontations risk losing good-time credit or transfer to higher security. "I know I don't belong here, I know I shouldn't be here, and I need to keep fighting to get out of here," Rodriguez writes. The letter lands as advocacy groups continue pushing for a pardon of both Rodriguez and co-developer William Hill, whose prosecution remains a landmark case testing whether building privacy tools constitutes a criminal act. Rodriguez can receive letters at FPC Morgantown, with mailing details available through The Rage.
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