Top-level domain name registry service on Google App Engine
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jianglai Add a Dockerfile to build the builder
Our Gradle build now requires three programs to build: Java, npm and gcloud. There are no existing images that contain all of them. Even if there were, they probably come from some random Joe on the Internet and we cannot trust the image to be free of malwares. Therefore we need to build our own builder.

The builder images will be built by Cloud Build and upload to our container registry. We should periodically rebuild it to pull in the latest security updates both for the base Ubuntu image, and for the components that we install. I have not figured out a way to do that yet. For now we'll just trigger Cloud Build manually once in a while.

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Latest commit 23ee5b2 Feb 14, 2019
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docs Explain SERVER_HOLD part of NAME_COLLISION reservations Feb 6, 2019
gradle Clean up the Gradle JS distribution a bit Feb 14, 2019
java Add admin page link to create new registrar Feb 14, 2019
python Split py_binary into py_binary and py_library to avoid having py_bina… Jan 25, 2019
third_party Update Nomulus to build with bazel 0.16.0 Aug 10, 2018
.gcloudignore Use gradlew in Cloud Build Dec 5, 2018
.gitignore Add gitignore rules for node modules Feb 14, 2019
.travis.yml Partially externalize WebDriver tests Feb 13, 2019
AUTHORS Change all references to Domain Registry to Nomulus Oct 14, 2016 Add Google Java Style Guide info and link to Nov 15, 2016
CONTRIBUTORS Export Weimin as author of commits to GitHub Jul 14, 2018
LICENSE Rename LICENSE.txt to LICENSE Jul 13, 2016 Fix travis build badge link Jan 8, 2019
WORKSPACE Add support to bazel 0.21.0 Dec 21, 2018
cloudbuild-proxy.yaml Use Maven repository on GCS for Cloud Build Feb 11, 2019
nomulus-logo.png Update Nomulus logo May 23, 2017


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Nomulus is an open source, scalable, cloud-based service for operating top-level domains (TLDs). It is the authoritative source for the TLDs that it runs, meaning that it is responsible for tracking domain name ownership and handling registrations, renewals, availability checks, and WHOIS requests. End-user registrants (i.e. people or companies that want to register a domain name) use an intermediate domain name registrar acting on their behalf to interact with the registry.

Nomulus runs on Google App Engine and is written primarily in Java. It is the software that Google Registry uses to operate TLDs such as .google, .app, .how, .soy, and .みんな. It can run any number of TLDs in a single shared registry system using horizontal scaling. Its source code is publicly available in this repository under the Apache 2.0 free and open source license.

Getting started

The following resources provide information on getting the code and setting up a running system:

If you are thinking about running a production registry service using our platform, please drop by the user group and introduce yourself and your use case. To report issues or make contributions, use GitHub issues and pull requests.


Nomulus has the following capabilities:

  • Extensible Provisioning Protocol (EPP): An XML protocol that is the standard format for communication between registrars and registries. It includes operations for registering, renewing, checking, updating, and transferring domain names.
  • DNS interface: The registry provides a pluggable interface that can be implemented to handle different DNS providers. It includes a sample implementation using Google Cloud DNS as well as an RFC 2136 compliant implementation that works with BIND.
  • WHOIS: A text-based protocol that returns ownership and contact information on registered domain names.
  • Registration Data Access Protocol (RDAP): A JSON API that returns structured, machine-readable information about domain name ownership. It is essentially a newer version of WHOIS.
  • Registry Data Escrow (RDE): A daily export of all ownership information for a TLD to a third party escrow provider to allow take-over by another registry operator in the event of serious failure. This is required by ICANN for all new gTLDs.
  • Premium pricing: Communicates prices for premium domain names (i.e. those that are highly desirable) and supports configurable premium registration and renewal prices. An extensible interface allows fully programmatic pricing.
  • Billing history: A full history of all billable events is recorded, suitable for ingestion into an invoicing system.
  • Registration periods: Qualified Launch Partner, Sunrise, Landrush, Claims, and General Availability periods of the standard gTLD lifecycle are all supported.
  • Brand protection for trademark holders (via TMCH): Allows rights-holders to protect their brands by blocking registration of domains using their trademark. This is required by ICANN for all new gTLDs.
  • Registrar support console: A self-service web console that registrars can use to manage their accounts in the registry system.
  • Reporting: Support for required external reporting (such as ICANN monthly registry reports, CZDS, Billing and Registration Activity) as well as internal reporting using BigQuery.
  • Administrative tool: Performs the full range of administrative tasks needed to manage a running registry system, including creating and configuring new TLDs.
  • DNS interface: An interface for DNS operations is provided so you can write an implementation for your chosen provider, along with a sample implementation that uses Google Cloud DNS. If you are using Google Cloud DNS you may need to understand its capabilities and provide your own multi-AS solution.
  • GAE Proxy: App Engine Standard only serves HTTP/S traffic. A proxy to forward traffic on EPP and WHOIS ports to App Engine via HTTPS is provided. Instructions on setting up the proxy on Google Kubernetes Engine is available. Running the proxy on GKE supports IPv4 and IPv6 access, per ICANN's requirements for gTLDs. The proxy can also run as a single jar file, or on other Kubernetes providers, with modifications.

Additional components

Registry operators interested in deploying Nomulus will likely require some additional components that are need to be configured separately.

  • A way to invoice registrars for domain name registrations and accept payments. Nomulus records the information required to generate invoices in billing events.
  • Fully automated reporting to meet ICANN's requirements for gTLDs. Nomulus includes substantial reporting functionality but some additional work will be required by the operator in this area.
  • A secure method for storing cryptographic keys. A keyring interface is provided for plugging in your own implementation (see configuration doc for details).
  • System status and uptime monitoring.

Outside references

  • Donuts Registry has helped review the code and provided valuable feedback
  • CoCCa and FRED are other open-source registry platforms in use by many TLDs
  • We are not aware of any fully open source domain registrar projects, but open source EPP Toolkits (not yet tested with Nomulus; may require integration work) include:
  • Some Open Source DNS Projects that may be useful, but which we have not tested: