Cashu Highlights Q2/25

Cashu is making steady progress, with several exciting new projects underway. This report provides an overview of the most recent updates and advancements from the second quarter of 2025, highlighting Multinut payments, a new Lightning payment type for Cashu wallets, and Chorus, a Nostr app designed for activists and community organizers that comes with a built-in Cashu wallet. We also present Routstr, a decentralized LLM routing marketplace, and Hashpool, an accountless Bitcoin mining pool. 

Multinut payments

Most Cashu wallets allow users to use more than just one mint, enabling them to split their balance across multiple mints for either convenience or to reduce the individual risk associated with using any singular mint. This poses a serious UX challenge when making Lightning payments with amounts larger than any individual balance the user may have on a single mint.

Multinut payments allow a user to pay a single Lightning invoice using funds from multiple mints at once. The invoice is split into parts, with each mint contributing a share of the total payment through its own Lightning node. These partial payments are coordinated using a Lightning feature called Multi-Path Payments (MPP), which merges them into a single transaction. The payment only succeeds if all parts are delivered; if any part fails, the entire transaction is canceled by the receiver.

Multinut payments reduce the reliance on a single mint operator and make it possible to complete payments even when no individual mint holds the full required amount. This reduces the risk for users since it allows them to spread their balance into smaller chunks across multiple mints without forcing them to shift around balances to make larger payments.

From a Cashu user’s perspective, all this is handled automatically for them. When a user scans a Lightning invoice that cannot be fully covered by a single mint, their wallet can execute a Multinut payment using their total balance across multiple mints.

Multinut payments demonstrate how new developments in the Cashu protocol can leverage advanced features in the underlying technology stack such as the Lightning Network’s ability to make multi-path payments.

Chorus

Chorus is an app built on Nostr designed by the newly founded And Other Stuff Collective to help communities create groups and raise funds through an integrated Cashu wallet. Launched at the Oslo Freedom Forum in May, it is specifically designed for activists and community organizers—individuals and groups who often face censorship from authoritarian governments or centralized social media platforms.

Chorus includes robust moderation features, allowing each group to independently define what content is permitted within their space. Users can easily create an account or log in using an existing Nostr private key and send Ecash to the groups they support.

Chorus combines Nostr’s decentralized, censorship-resistant messaging with Cashu’s privacy-preserving payments, enabling permissionless communication and instant, privacy-preserving transactions. The result is a platform that empowers communities to organize, communicate, and fundraise—even under repressive conditions.

Routstr 

Routstr is a decentralized AI marketplace that leverages Nostr for the discovery of large language model (LLM) providers and Cashu for anonymous microtransactions—enabling users and providers to easily monetize AI model access.

This is how it works: Users acquire Cashu tokens by paying with Bitcoin, either via the Lightning Network or on-chain—no account or sign-up is required. These tokens act as prepaid API keys for accessing Routstr’s AI models.

Anyone can provide AI models on Routstr. A Routstr proxy is deployed in front of any OpenAI-compatible endpoint. This proxy manages API requests, tracks usage, and validates tokens. AI providers can run their own Cashu mint and Lightning node or use any other mint they want.

This system enables pay-per-use AI chat through instant, anonymous Bitcoin micropayments with Cashu, all without the need for accounts. In the future, we could see software products that come with built-in AI tools that do not require their users to first create an account with a third-party AI provider, and copy and paste API keys. Simply top up with Bitcoin and start vibing.

Hashpool

In a similar vein, the Hashpool project has garnered a lot of interest in the last quarter. Hashpool is an accountless mining pool that uses Ecash to represent mining shares. You can read more about it in a recently published article.

Unlike traditional mining pools—which usually require KYC (Know Your Customer) verification—Hashpool offers a privacy-preserving alternative. Even if KYC is not enforced, conventional pools still track sensitive data such as IP addresses, hashrate, and payout information.

Additionally, minimum withdrawal limits and onboarding fees make it difficult for small miners to participate in traditional pools.

Hashpool resolves this by issuing Ecash tokens for mining shares, called eHash, eliminating the need to maintain individual user balances in a database. Only the number of tokens in circulation is known. Thanks to Cashu’s efficiency, Hashpools can operate without onboarding fees, as long as the instance supports Ecash payouts.

Together, Cashu and Hashpool are making Bitcoin mining more private, lowering barriers to entry, and simplifying the setup process. This also expands participation opportunities for smaller miners.

Wrap-up

The second quarter of 2025 has marked significant progress, demonstrating the Cashu protocol’s utility across various contexts.

A key protocol development is the introduction of Multinut payments, which allows users to pay a single Lightning invoice from multiple mints. This reduces dependence on a single mint, improving transaction reliability and flexibility.

The built-in Cashu wallet in the Chorus app highlights its benefits for communities, empowering activists and organizers to fundraise.

The integration of Cashu in Routstr enables a decentralized AI marketplace through microtransactions, allowing for account-free access and monetization of AI use.

The integration of Cashu in Hashpool opens new opportunities for miners by providing a privacy-preserving alternative to traditional mining pools.

Overall, Cashu is addressing the increasing demand for privacy and fast transactions across the web, gaining growing relevance in and outside of the Bitcoin ecosystem. The current developments not only enhance the user experience but also create opportunities in integrating Cashu into other Internet applications.