Terms of Service, Privacy Policy, Disclaimer, and Open-Source Licenses for the Anvil project. Last updated: April 2, 2026.
By accessing, downloading, installing, or using Anvil ("the Software"), you agree to be bound by these Terms of Service ("Terms"). If you do not agree to these Terms, you must not use the Software. These Terms constitute a legally binding agreement between you ("User," "you," or "your") and the Anvil project contributors ("we," "us," or "our").
Anvil is an open-source educational software project designed to demonstrate and teach how blockchain technology works at a fundamental level. It is a sandbox environment that creates a simulated blockchain running entirely on your local machine or local network. The Software is not, and is not intended to be, a production-grade blockchain, cryptocurrency, distributed ledger, or financial system of any kind.
The native coin "ANV" (or any custom coin name configured by the user) is a simulated digital token that exists only within the Software's local runtime. ANV coins:
Anvil is not any of the following:
Nothing in this Software, its documentation, landing page, or associated materials constitutes financial advice, investment advice, trading advice, or any other sort of professional advice. You should not make any financial decision based on anything related to this project.
The Software is intended exclusively for:
You are free to modify, fork, and redistribute the Software under the terms of the MIT License. However, if you create a derivative work, you are solely responsible for ensuring that your derivative work complies with all applicable laws and regulations in your jurisdiction, including but not limited to securities laws, money transmission laws, and consumer protection regulations.
While we strive to implement blockchain concepts correctly for educational purposes, we make no guarantee that the Software perfectly replicates the behavior of any specific production blockchain (e.g., Bitcoin, Ethereum). Certain features are intentionally simplified for clarity, as documented in the README.
These Terms are effective until terminated. Your rights under these Terms will terminate automatically if you fail to comply with any of their provisions. Upon termination, you must cease all use of the Software and destroy all copies in your possession.
These Terms shall be governed by and construed in accordance with applicable laws, without regard to conflict of law principles. Any disputes arising out of these Terms or the use of the Software shall be resolved through good-faith negotiation.
We reserve the right to modify these Terms at any time. Changes will be reflected by updating the "Last updated" date at the top of this page. Your continued use of the Software after changes constitutes acceptance of the revised Terms.
Anvil does not collect, process, transmit, store, or share any personal data, usage data, analytics, telemetry, crash reports, or any other information about you or your system. The Software runs entirely on your local machine with zero network calls to external services (other than peer nodes you explicitly configure on your own local network).
The following data is stored locally on your machine and never leaves it:
wallets/ directorynode_modules/)No data is persisted to disk beyond wallet key files unless you explicitly implement such functionality.
When you run the multi-node feature, nodes communicate over HTTP on your local machine (localhost). This communication:
Anvil does not integrate with, send data to, or receive data from any third-party services, analytics platforms, advertising networks, or external APIs. The Software has one runtime dependency (Express.js) which is used solely as a local HTTP server and does not perform any data collection.
The Anvil landing page (this website) does not use cookies, local storage, session storage, tracking pixels, fingerprinting, or any other client-side tracking mechanism. No analytics scripts are loaded.
Anvil does not knowingly collect any information from anyone, including children under the age of 13 (or the applicable age in your jurisdiction). Since the Software collects no data at all, there is no risk of children's data being collected.
Since Anvil does not collect, process, or store any personal data, the typical obligations under the General Data Protection Regulation (GDPR), California Consumer Privacy Act (CCPA), and similar data protection regulations do not apply in the traditional sense. There is no data to access, delete, port, or restrict processing of.
If we ever modify Anvil to include any form of data collection (which is not planned), we will update this Privacy Policy before implementing such changes and clearly communicate the modifications.
THE SOFTWARE IS PROVIDED "AS IS" AND "AS AVAILABLE," WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND NONINFRINGEMENT. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU.
IN NO EVENT SHALL THE AUTHORS, COPYRIGHT HOLDERS, CONTRIBUTORS, OR ANY AFFILIATED PARTIES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, CONSEQUENTIAL, OR PUNITIVE DAMAGES (INCLUDING BUT NOT LIMITED TO PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, LOSS OF USE, DATA, OR PROFITS, OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
While Anvil uses real cryptographic primitives (SHA-256 for hashing, Ed25519 for digital signatures), the overall system architecture is intentionally simplified for educational purposes. Known security limitations include but are not limited to:
Do not use this Software to secure anything of value. It is designed for learning, not production use.
Mention of any specific blockchain project (Bitcoin, Ethereum, etc.) in documentation or code comments is purely for educational comparison purposes and does not constitute an endorsement of, association with, or affiliation with those projects.
Users are solely responsible for determining whether their use of the Software complies with applicable laws and regulations in their jurisdiction. While Anvil itself is not a regulated financial product, modifications or derivative works may fall under financial regulations depending on how they are used.
You may use the Software for:
You must not use the Software to:
You must not misrepresent the nature of this Software. If you create derivative works, educational content, or presentations based on Anvil, you must clearly state that it is an educational sandbox and that ANV coins have no monetary value.
Anvil welcomes contributions from the community. By submitting a pull request, issue, or any other form of contribution to the Anvil repository, you agree to the following terms.
By contributing code, documentation, or other materials to the Anvil project, you grant the project maintainers a perpetual, worldwide, non-exclusive, royalty-free, irrevocable license to use, reproduce, modify, display, distribute, and sublicense your contribution as part of the Software under the MIT License.
You represent that each of your contributions is your original creation and that you have the legal right to grant the license described above. If your contribution includes work created by others, you must clearly identify the source and ensure it is compatible with the MIT License.
The project maintainers are under no obligation to accept, merge, or maintain any contribution. Contributions may be modified, rewritten, or removed at the maintainers' discretion.
Contributors are expected to maintain a respectful and constructive environment. Harassment, discrimination, and disruptive behavior will not be tolerated.
Anvil is educational software with known security limitations (see Section 3.3). "Security vulnerabilities" in the context of this project refer to issues that could:
Issues related to the educational simplifications listed in Section 3.3 (e.g., "the chain doesn't use Merkle trees") are not considered security vulnerabilities -- they are intentional design decisions for educational clarity.
If you discover a security issue within the scope defined above, please report it by opening an issue on the GitHub repository or contacting the maintainers directly. Do not exploit the vulnerability or disclose it publicly before giving us a reasonable opportunity to address it.
We will make reasonable efforts to address legitimate security reports in a timely manner. However, as this is an educational project maintained by volunteers, we cannot guarantee specific response times or SLAs.
The Anvil project is released under the MIT License, one of the most permissive open-source licenses available.
Anvil uses the following third-party open-source software. Each is distributed under its own license, included below. Anvil has a single runtime dependency (Express.js), which in turn depends on several sub-packages. The key licenses are listed here.
All MIT-licensed dependencies grant permission to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the software, provided the copyright notice and permission notice are included.
Anvil runs on Node.js, which is not bundled with the Software but is required as a runtime. Node.js is licensed under the following terms:
Node.js also includes components under various other licenses (ICU, V8, libuv, OpenSSL, zlib, etc.). For the complete license information, see the Node.js repository at github.com/nodejs/node.
Express.js is the sole runtime dependency of Anvil, used for the node HTTP server feature.
Anvil uses the built-in Node.js crypto module for SHA-256 hashing and Ed25519 digital signatures. The Node.js crypto module is powered by OpenSSL (or BoringSSL / quictls depending on the Node.js build).
This Software includes cryptographic functionality. Depending on your jurisdiction, the import, export, or use of cryptographic software may be subject to regulation. You are solely responsible for complying with any such restrictions in your jurisdiction. The cryptographic functionality in Anvil is provided by the Node.js runtime, which you install separately.
Both algorithms are well-established, widely reviewed, and considered secure for their intended purposes. However, as noted in Section 3.3, the system architecture around these primitives is simplified for educational purposes and should not be relied upon for security.
OpenSSL is licensed under the Apache License 2.0 (as of OpenSSL 3.0). For the full license text, see openssl.org/source/license.html.
The name "Anvil" as used in this project refers solely to this open-source educational blockchain software. It is not a registered trademark. The project makes no claim to exclusivity over the name.
All other trademarks, trade names, and brand names mentioned in the Software, documentation, or this page (including but not limited to Bitcoin, Ethereum, Node.js, Express.js, GitHub, and SHA-256) are the property of their respective owners and are used here solely for identification and educational reference purposes. Their use does not imply endorsement, sponsorship, or affiliation.
For questions about these Terms, the Privacy Policy, or the Anvil project in general:
For security issues, please see Section 6 (Security Policy).