Zoe: the Smart Contract Framework for Offer Enforcement

Usage no npm install needed!

<script type="module">
  import agoricZoe from 'https://cdn.skypack.dev/@agoric/zoe';



Agoric Platform SDK

This repository contains most of the packages that make up the upper layers of the Agoric platform, with the endo repository providing the lower layers. If you want to build on top of this platform, you don't need these repositories: instead you should follow our instructions for getting started with the Agoric SDK.

But if you are improving the platform itself, these are the repositories to use.


  • Git
  • Node.js LTS (version 14.15.0 or higher)
    • we generally support the latest LTS release: use nvm to keep your local system up-to-date
  • Yarn (npm install -g yarn)

Any version of Yarn will do: the .yarnrc file should ensure that all commands use the specific checked-in version of Yarn (stored in .yarn/releases/), which we can update later with PRs in conjunction with any necessary compatibility fixes to our package.json files.

Building on Apple Silicon and Newer Architectures

Some dependencies may not be prebuilt for Apple Silicon and other newer architectures, so it may be necessary to build these dependencies from source and install that package’s native dependencies with your package manager (e.g. Homebrew).

Currently these dependencies are:

Additionally, if your package manager utilizes a non-standard include path, you may also need to export the following environment variable before running the commands in the Build section.

export CPLUS_INCLUDE_PATH=/opt/homebrew/include

Finally, you will need the native build toolchain installed to build these items from source.

xcode-select --install


From a new checkout of this repository, run:

  • yarn install
  • yarn build

When the yarn install is done, the top-level node_modules/ will contain all the shared dependencies, and each subproject's node_modules/ should contain only the dependencies that are unique to that subproject (e.g. when the version installed at the top level does not meet the subproject's constraints). Our goal is to remove all the unique-to-a-subproject deps.

When one subproject depends upon another, node_modules/ will contain a symlink to the subproject (e.g. ERTP depends upon marshal, so node_modules/@endo/marshal is a symlink to packages/marshal).

Run yarn workspaces info to get a report on which subprojects (aka "workspaces") depend upon which others. The mismatchedWorkspaceDependencies section tells us when symlinks could not be used (generally because e.g. ERTP wants marshal@0.1.0, but packages/marshal/package.json says it's actually 0.2.0). We want to get rid of all mismatched dependencies.

The yarn build step generates kernel bundles.


To run all unit tests (in all packages):

  • yarn test (from the top-level)

To run the unit tests of just a single package (e.g. eventual-send):

  • cd packages/eventual-send
  • yarn test

Run the larger demo

Visit https://agoric.com/documentation/ for getting started instructions.


  • yarn link-cli ~/bin/agoric
  • cd ~
  • agoric init foo
  • cd foo
  • agoric install
  • agoric start

Then browse to http://localhost:8000

Edit Loop

  • modify something in e.g. zoe/
  • run yarn build (at the top level or in zoe/)
  • re-run tests or agoric start --reset
  • repeat

Doing a yarn build in zoe creates the "contract facet bundle", a single file that rolls up all the Zoe contract vat sources. This bundle file is needed by all zoe contracts before they can invoke zoe~.install(...). If you don't run yarn build, then changes to the Zoe contract facet will be ignored.

Development Standards

  • All work should happen on branches. Single-commit branches can land on trunk without a separate merge, but multi-commit branches should have a separate merge commit. The merge commit subject should mention which packages were modified (e.g. (SwingSet,cosmic-swingset) merge 123-fix-persistence)
  • Keep the history tidy. Avoid overlapping branches. Rebase when necessary.
  • All work should have an Issue. All branches names should include the issue number as a prefix (e.g. 123-description). Use "Labels" on the Issues to mark which packages are affected.
  • Add user-visible changes to a new file in the changelogs/ directory, named after the Issue number. See the README in those directories for instructions.
  • Unless the issue spans multiple packages, each branch should only modify a single package.
  • Releases should be made as according to MAINTAINERS.md.

Adding a new package

To create a new (empty) package (e.g. spinning Zoe out from ERTP):

  • mkdir packages/zoe
  • add your sources/tests/etc to packages/zoe/src/ etc
  • populate a new packages/zoe/package.json, using other packages as a template
  • edit the top-level package.json to add packages/zoe to "workspaces"
  • run yarn install, and commit the resulting changes to yarn.lock
  • check the output of yarn workspaces info to make sure there are no mismatchedWorkspaceDependencies, adjust the new package's dependencies until they are correctly satisfied by the other local packages
  • edit .github/workflows/test-all-packages.yml to add a clause that tests the new package
  • commit everything to a new branch, push, check the GitHub Actions tab to make sure CI tested everything properly
  • merge with a PR