Satoshi Scoop Weekly, 15 August 2025

Crypto Insights#

In recent years, Bitcoin's mempool policies have shown notable divergence, such as full adoption of Replace-by-Fee, various Knots spam filtering options, uncapped datacarrier/OP_RETURN limits, and the 0.1 sat/vB minimum fee.

To mitigate issues caused by divergent mempool policies, Anthony Towns suggested that Bitcoin full nodes occasionally share their current template for the next block. Using compact block relay encoding, a node could send its latest template for the next block; the receiving peer would then request any missing transactions from that template, either adding them to its mempool if they meet local policy or caching them for potential use. This allows nodes with different mempool policies to still synchronize high-fee transactions and improve block reconstruction performance. This proposal is an alternative to the earlier "weak blocks" concept. Towns has also released a proof-of-concept implementation.

A Decade in the Making: Simplicity Powers a Programmable Bitcoin Future#

According to Blockstream's Andrew Poelstra, the smart contract language Simplicity—ten years in development—will be deployed on Bitcoin testnet by late 2025 or early 2026. Simplicity represents a revolutionary approach to Bitcoin smart contracts, offering formal security guarantees and the ability to express arbitrary computation, while maintaining Bitcoin's predictable fee model and decentralization principles. Unlike Ethereum's trade-offs, Simplicity supports covenants, vaults, zero-knowledge proof verification, and advanced financial primitives without compromising security or introducing DoS risks.

Andrew also explained how Simplicity HL offers developers a Rust-like programming experience, compiling into mathematically provable Simplicity code—unlocking new possibilities for Discreet Log Contracts, delegations, and programmable Bitcoin transactions.

Starkware: Building STARKs in Simplicity#

In this article, Starkware shares its ideas on combining Simplicity with STARKs. Simplicity is similar to Rust but more minimal and easier to learn. Key features include:

It is not Turing-complete—allowing precise analysis of what a program will do before it runs.
It uses a mechanism called Jets to accelerate execution. Jets act like "fast-forward buttons" for common operations (e.g., SHA-256, ECDSA). When developers write in Simplicity, optimized C code runs silently underneath.
It runs on a virtual machine called the Bit Machine, allowing predictable computation costs—especially useful for limited-resource contexts like Bitcoin blocks.

Starkware believes Simplicity is expressive enough to write STARK verifiers. Developers could use Simplicity to prove off-chain computations (e.g., complex contracts or privacy-preserving payments) and verify them on Bitcoin or the sidechain Liquid.

Bitle: Solar-Powered Relay Node for Bitchat#

Bitle is a self-powered relay node designed to support Bitchat, a Bluetooth mesh networking messaging app by Jack Dorsey that works without an internet connection.

Bitle relays encrypted messages between devices, extending Bitchat’s offline communication range. Operating as a passive mesh node, it increases network coverage without appearing as a directly connected node in the Bitchat UI. Bitle can run indefinitely on solar power, or for 25–50 days on battery alone, with an estimated communication range of 300–500 feet.

PayPerQ: Pay-Per-Query Chatbot via Lightning Payments#

PayPerQ is an AI chatbot platform supporting Lightning Network micropayments. It allows users to access ChatGPT or Claude on a pay-per-query basis, without subscriptions or credit cards.

Alby: Building Conditional Payment Logic into Apps#

Hold introduces the significance of Hold invoices for Lightning developers. They allow control over the final settlement time of a Lightning payment, enabling conditional payments, deposit mechanisms, and non-custodial escrow transactions—enhancing security and flexibility.

With Alby Hub and the NWC API, developers can easily create, monitor, settle, and cancel Hold invoices within apps—without running their own Lightning infrastructure.

Bitcoin-MCP: Creating AI Agents with Lightning Network Access#

Bitcoin-MCP (GitHub repo) is a Model Context Protocol (MCP) server enabling AI models to interact with Bitcoin and the Lightning Network—generating keys, verifying addresses, decoding transactions, querying the blockchain, and more.

FPPS Mining Unsustainable? A Decentralization Turning Point for Bitcoin?#

Rob Warren predicts that the current centralized mining landscape—where just two pools control over 60% of network hashrate—will undergo a major shift in 4–6 years. He argues that the Full Pay Per Share (FPPS) pool model may not survive as Bitcoin’s incentives shift from block subsidies to a fee-based revenue structure. The reason: pool fees required to offer FPPS could become so high that miners would be better off taking on variable risk directly.

Emergency Upgrade and Multisig Mechanisms in BitVM Bridges#

BitVM bridges are evolving, with many operators and liquidity providers requesting an "emergency path" to move funds if vulnerabilities are found. This has led to the introduction of emergency multisig as an alternative spend path, along with a "security council"—a permissioned group of signers authorized to operate the emergency multisig, able to move funds out of the bridge instance directly, bypassing the challenge game and optimistic settlement mechanisms.

However, Janusz points out technical risks, exploring both the emergency upgrade plan and multisig mechanism. He notes that such spend paths cannot be verified on-chain ahead of time—they only become visible when spent. This means that if participants never disclose them, some users may never realize that a BitVM bridge's ultimate trust model is actually a permissioned M-of-N multisig.

Fairgate Launches FLEX: Garbled-Circuit Fraud Prevention for Bitcoin Bridges#

Fairgate introduced FLEX, a new fraud-proofs system for Bitcoin bridges that does not require large, permanent security bonds. Built with garbled circuits and compatible with the BitVM and BitVMX ecosystems, FLEX supports on-demand security bonds only activated in the event of a dispute.

Alpen Labs Launches EVM-Compatible BitVM Testnet#

Alpen Labs launched a public testnet with an EVM-compatible environment and BitVM2-inspired verifier, enabling EVM developers to leverage existing EVM infrastructure for Bitcoin development.