Plutus Platform

Table of Contents

• How to use the project
  • Prerequisites
  • How to get started using the libraries
  • How to build the Haskell packages and other artifacts
  • How to run a local Plutus Playground in a Docker container
  • How to get the most recent documentation PDFs from CI
• Where to go next
  • Where to find tutorials
  • How to learn about the terminology we use
  • Where to find the changelog
  • How to submit an issue
  • How to communicate with us
  • How to develop and contribute to the project
• Nix
  • How to set up the IOHK binary caches
  • Nix on macOS
  • Which attributes to use to build different artifacts

The Plutus Platform enables you to:

• Work with Plutus Core, the smart contract language embedded in the Cardano ledger.

• Write Haskell programs that create and use embedded Plutus Core programs using Plutus Tx.

• Write smart contract executables which can be distributed for use with the Plutus Smart Contract Backend.

You are free to copy, modify, and distribute the Plutus Platform with under the terms of the Apache 2.0 license. See the LICENSE and NOTICE files for details.

How to use the project

This section contains brief information about how to use this project. For development work see How to develop and contribute to the project for more information.

Prerequisites

The Haskell libraries in the Plutus Platform can be built in a number of ways. The prerequisites depend on how you want to build the libraries. The other artifacts (docs etc.) are most easily built with Nix, so we recommend installing it regardless.

• Nix (recommended).

  • Install Nix following the instructions on the Nix website.

    Important

    Even if you already have Nix installed, make sure to set up the IOHK binary cache.

  • See Nix for further advice on using Nix.

• cabal (if building Haskell packages with cabal).

• stack (if building Haskell packages with stack).

How to get started using the libraries

There is an example project in the example folder, see its README for more details.

How to build the Haskell packages and other artifacts

How to build Haskell packages and other artifacts with Nix

Run nix build -f default.nix haskell.projectPackages.language-plutus-core from the root to build the Plutus Core library.

See Which attributes to use to build different artifacts to find out what other attributes you can build.

How to build Haskell packages with cabal

Run cabal v2-build language-plutus-core from the root to build the Plutus Core library.

See the cabal project file to see the other projects that you can build with cabal.

How to build the Haskell packages with stack

Run stack build language-plutus-core from the root to build the Plutus Core library.

See the stack project file to see the other projects that you can build with stack.

How to run a local Plutus Playground in a Docker container

1. Install Docker following the instructions on the Docker website.

2. Run nix build -f default.nix docker.plutusPlaygroundImage, to build

3. Run docker load < docker-image-plutus-playgrounds.tar.gz - this will print out the image name at the end, e.g. Loaded image: plutus-playgrounds:yn7h7m5qdjnnj9rxv8cgkvvwjkkcdnvp

4. Run docker run --mount ‘type=bind,source=/tmp,target=/tmp’ -p 8080:8080 plutus-playgrounds:yn7h7m5qdjnnj9rxv8cgkvvwjkkcdnvp using the image name from the previous step.

5. Open http://localhost:8080/ in a web browser.

How to get the most recent documentation PDFs from CI

Specifications and design

• Plutus Technical Report (draft)

• Plutus Core Specification

• Extended UTXO Model

Academic papers

• Unraveling Recursion (published version)

• System F in Agda (published version)

• The Extended UTXO Model (in press)

Where to go next

Where to find tutorials

The doc folder contains the documentation site.

To build a full HTML version of the site that you can view locally, build the docs.site attribute using Nix.

How to learn about the terminology we use

There is a comprehensive glossary in GLOSSARY.

Where to find the changelog

The changelog is stored in CHANGELOG.

How to submit an issue

We track our issues on the GitHub Issue tracker.

How to communicate with us

We’re active on the Cardano forum. Tag your post with the plutus tag so we’ll see it.

Use the Github issue tracker for bugs and feature requests, but keep other discussions to the forum.

How to develop and contribute to the project

See CONTRIBUTING, which describes our processes in more detail including development environments; and ARCHITECTURE, which describes the structure of the repository.

Nix

How to set up the IOHK binary caches

Adding the IOHK binary cache to your Nix configuration will speed up builds a lot, since many things will have been built already by our CI.

If you find you are building packages that are not defined in this repository, or if the build seems to take a very long time then you may not have this set up properly.

To set up the cache:

1. On non-NixOS, edit /etc/nix/nix.conf and add the following lines:

   substituters        = https://hydra.iohk.io https://iohk.cachix.org https://cache.nixos.org/
   trusted-public-keys = hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ= iohk.cachix.org-1:DpRUyj7h7V830dp/i6Nti+NEO2/nhblbov/8MW7Rqoo= cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=

2. On NixOS, set the following NixOS options:

   nix = {
     binaryCaches          = [ "https://hydra.iohk.io" "https://iohk.cachix.org" ];
     binaryCachePublicKeys = [ "hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=" "iohk.cachix.org-1:DpRUyj7h7V830dp/i6Nti+NEO2/nhblbov/8MW7Rqoo=" ];
   };

Note	If you are a trusted user you may add the nix.conf lines to ~/.config/nix/nix.conf instead.

Nix on macOS

Nix on macOS can be a bit tricky. In particular, sandboxing is disabled by default, which can lead to strange failures.

These days it should be safe to turn on sandboxing on macOS with a few exceptions. Consider setting the following Nix settings, in the same way as in previous section:

sandbox = true
extra-sandbox-paths = /System/Library/Frameworks /System/Library/PrivateFrameworks /usr/lib /private/tmp /private/var/tmp /usr/bin/env

Which attributes to use to build different artifacts

default.nix defines a package set with attributes for all the artifacts you can build from this repository. These can be built using nix build. For example:

nix build -f default.nix haskell.projectPackages.language-plutus-core

Example attributes

• Project packages: defined inside haskell.projectPackages

  • e.g. haskell.projectPackages.language-plutus-core

• Documents: defined inside docs

  • e.g. docs.plutus-core-spec

• Development scripts: defined inside dev

  • e.g. dev.scripts.fixStylishHaskell

There are other attributes defined in default.nix.