Mops

August 20, 2026 · View on GitHub

Mops is a package manager for the Motoko programming language.

Setup

Mops downloads and manages the Motoko toolchain itself. It does not need dfx, and does not support it.

curl -fsSL cli.mops.one/install.sh | sh

npm i -g ic-mops

Run this command in the root directory of your project

mops init

Every command that compiles uses the moc pinned in mops.toml

mops toolchain use moc latest

Use mops add <package_name> to install a specific package and save it to mops.toml

mops add core

You can also add packages from GitHub like this

mops add https://github.com/dfinity/motoko-base

For GitHub-packages you can specify branch, tag, or commit hash by adding #<branch/tag/hash>

mops add https://github.com/dfinity/motoko-base#moc-0.9.1

You can also add local packages like this (put source files inside src directory)

mops add ./shared

Use mops install to install all packages specified in mops.toml

mops install

Now you can import installed packages in your Motoko code

import PackageName "mo:<package_name>";

for example

import Itertools "mo:itertools/Iter";

Import an existing secp256k1 or Ed25519 private key into mops

mops user import -- "$(icp identity export mops)"

Run this command in your package root and select type "Package"

mops init

Edit description and repository fields in mops.toml file.

Write your package code in *.mo source files in the src/ directory.

Create README.md file with information on how to use your package.

Publish package to the mops registry!

mops publish