Cashu Development Kit (CDK) is a free, MIT-licensed set of Rust components for building and running Cashu software. It is aimed at developers, mint operators and technically minded users who want a command-line wallet or a server that issues and redeems Cashu tokens.
The project is a CLI wallet and mint daemon rather than a point-and-click app. Its latest release is v0.18.3, and the repository was last updated in October 2026. It supports Bitcoin (BTC), the Lightning Network and Nostr, and it offers several storage and Lightning backend options. Below you will find what each part does, how to install the ready-made program and what to check before using it with real funds.
What Is Cashu and How Does It Work?
Cashu is a protocol for ecash-style tokens that represent value held by a server called a mint. A user who receives tokens can keep them in a wallet and later exchange them with the mint for other payments. The design aims to limit how much the mint can learn about who holds which token.
The key idea is that the mint signs tokens without seeing their link to a specific payer, using a technique called a blind signature. When someone spends a token, the mint checks that the signature is valid and that the token has not been spent before. This means a wallet and a mint each do a clearly defined job.
Cashu Development Kit provides the building blocks for both sides of that exchange. Wallet software handles storing and spending tokens, while mint software issues them and connects to Lightning or on-chain Bitcoin for funding and withdrawals. Understanding this split helps you decide which part of the kit you actually need.
Who Is Cashu Development Kit For?
The most obvious audience is developers who want to build Cashu-based applications in Rust. Instead of writing the protocol from scratch, they can start from a shared implementation and focus on their product, such as a payment flow, a merchant integration or a tool for managing balances.
Mint operators form a second group. A small community or a project team might want to run its own mint for a specific group of users, and the daemon components give them a starting point. Choosing a storage backend and a Lightning node is part of that setup, and the options in the kit cover common choices.
Technically curious users who want to test the protocol on their own machine also benefit. A local SQLite setup with a command-line wallet is a low-stakes way to see how tokens move between a wallet and a mint before deciding whether a larger project makes sense.
Key Terms Behind Cashu Tools
A mint is the server that issues tokens and redeems them. A wallet is the client that holds tokens and sends them to others. Many people confuse the two, but they serve different purposes, and running one does not automatically mean you are running the other.
Lightning invoices are payment requests generated on the Lightning Network. When a mint pays or receives funds over Lightning, the relevant backend, such as CLN, LND or LDK Node, creates or pays these invoices. On-chain Bitcoin transactions, by contrast, settle directly on the Bitcoin blockchain and usually take longer to confirm.
A storage backend holds the data that a wallet or mint needs to keep working, including token records and balances. Choosing a backend affects how the data is stored and shared. Keeping regular backups of whichever database you use is a practical habit that applies to all of them.
Key features
Core Protocol Library (cashu)
Rust Implementation (cdk)
SQLite Storage (cdk-sqlite)
PostgreSQL Storage (cdk-postgres)
Redb Storage (cdk-redb)
Supabase Storage (cdk-supabase)
Axum Web Server (cdk-axum)
Core Lightning Backend (cdk-cln)
LND Lightning Backend (cdk-lnd)
LDK Node Lightning Backend (cdk-ldk-node)
On-chain Bitcoin Backend (cdk-bdk)
Supported coins
The documentation mentions Bitcoin (BTC), the Lightning Network and Nostr. Through the Lightning and on-chain Bitcoin backends, a mint can process Lightning payments and regular Bitcoin transactions. Which network a given setup uses depends on the backend an operator configures.
How to install Cashu Development Kit on Windows
- 1
Get the program from the official source
Open the project's GitHub Releases page at github.com/cashubtc/cdk and look for the latest release, currently v0.18.3. Download the Windows file if one is listed. Download only from the official website or GitHub repository, and avoid mirrors or copies shared on forums and chat apps.
- 2
Verify the file
Check the SHA-256 checksum of the downloaded file against the value published with the release. If the release provides a signature, verify that as well. A mismatch means the file may be corrupted or altered, and it should not be run.
- 3
Install and run
Extract or install the program into a folder you control, then open a terminal in that location. Run the program's help command first to see the available subcommands before you create a wallet or start a mint.
-
Build from source if no Windows file is listed
Windows builds are listed as likely rather than guaranteed, so the Releases page may not include a ready-made Windows file for every version. In that case, you can build the project from its source code. Building requires a Rust toolchain and is a developer task, not a requirement for running the released program.
How to use Cashu Development Kit
The kit is driven from the command line, so the workflow starts in a terminal rather than a graphical window. The steps below describe a typical first session with a local setup.
- Confirm that the program runs by checking its help output and noting the available subcommands.
- Decide on a storage backend for your test, such as SQLite for a single local file.
- Create or initialize a wallet using the command shown in the help text, and store any recovery material in a safe offline location.
- Request a small amount of test value from a mint you control, or connect to a test environment you trust, before using any real funds.
- Send and receive a small payment to confirm that the wallet and mint behave as expected.
- Review the logs and balances, then back up your data before making changes.
If you plan to run a mint, add a Lightning or on-chain backend that matches your infrastructure, and test it end to end before opening it to other users.
Pros & cons
- Free and MIT-licensed, so the code can be read, reused and modified
- Several storage backends, including SQLite, PostgreSQL, Redb and Supabase
- Multiple Lightning backends, including CLN, LND and LDK Node
- An on-chain Bitcoin backend built with BDK covers regular transactions
- Written in Rust, with a typed API for developers embedding the protocol
- Recent code activity, with the latest version at v0.18.3
- Command-line focused, so it is not suited to users who want a graphical wallet
- Windows availability is listed as likely rather than guaranteed
- Running a mint requires technical knowledge of databases and Lightning nodes
- Version numbers below 1.0 often mean interfaces can still change between releases
- Not a consumer product with polished onboarding for everyday payments
Is Cashu Development Kit safe?
Cashu Development Kit handles wallet keys and, in mint mode, real user funds, so treat security as a priority. Download the program only from the official GitHub repository and its Releases page. Check the SHA-256 checksum or signature of the file before running it. Verify the latest version on the official website, since older builds may lack fixes.
Never enter a seed phrase or recovery material on a third-party website, in a chat or in an email. Store backups offline and separate from the machine running the software. If you operate a mint, you are responsible for the security of the funds it holds, so restrict access to the server and keep its databases backed up. Test with small amounts first.
- Official source only. Download from github.com/cashubtc/cdk. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Electrum, Sparrow Wallet and Wasabi Wallet are Bitcoin wallets designed for people who want to hold and move bitcoin directly. They come with graphical interfaces and focus on the wallet experience, including hardware wallet support and, in some cases, Lightning or CoinJoin features. Bitcoin Safe is aimed at long-term storage with a simpler setup.
Cashu Development Kit works differently. It is a developer toolkit centered on the Cashu protocol, offering a command-line wallet and mint components rather than a general-purpose desktop wallet. If your goal is to hold everyday bitcoin, a mature Bitcoin wallet is usually the better fit. If your goal is to build or run Cashu infrastructure, this kit is the more relevant choice.
Specifications
- Price
- Free
- Type
- Open source
- License
- MIT
- Latest version
- v0.18.3
- Last update
- 29 Oct 2026
- Windows support
- Likely (builds for Windows; check releases)
- Source code
- github.com/cashubtc/cdk
Frequently asked questions
Cashu Development Kit is used to build and run software based on the Cashu protocol. It includes a command-line wallet and components for running a mint, including storage backends and Lightning or on-chain Bitcoin connections. Developers and mint operators are its main audience.
Yes, the program is free and released under the MIT license. The source code is publicly available on GitHub, so you can read it, reuse it and modify it under the terms of that license.
Windows builds are listed as likely, so the project is expected to build for Windows. Check the Releases page for the current version to see whether a Windows file is provided. If not, you can build the project from source using a Rust toolchain.
Not necessarily. Rust is needed to build the project from source. If a ready-made Windows file is available on the Releases page, you can run it without installing a Rust toolchain, although you will still need a terminal.
A Cashu mint is a server that issues Cashu tokens against funds it receives and redeems those tokens when users spend them. Running a mint means holding and managing real value for others, so it requires careful setup, backups and attention to security.
The kit includes Lightning backends for Core Lightning (CLN), LND and LDK Node. An operator chooses one backend that matches the Lightning node they already run or plan to run. The backend connects the mint to that node for paying and receiving Lightning payments.
It can be, but safety depends on where you download the software, how you verify it and how you protect your keys. Use only the official GitHub source, check the checksum or signature, and test with small amounts first. The safety section above lists the steps in more detail.
Verdict
Cashu Development Kit suits developers building Cashu applications and technically experienced operators who want to run a mint. It gives you a Rust protocol implementation, several storage and Lightning backends, and a command-line wallet under a permissive license. It is not a good choice for someone who wants a simple graphical wallet for everyday bitcoin. Test thoroughly with small amounts before relying on it for anything important.