A tool for managing Dart projects with multiple packages, inspired by Lerna.
Splitting up large code bases into separate independently versioned packages is extremely useful for code sharing. However, making changes across many repositories is messy and difficult to track, and testing across repositories gets complicated really fast.
To solve these (and many other) problems, some projects will organize their code bases into multi-package repositories (sometimes called monorepos)
Melos is a tool that optimizes the workflow around managing multi-package repositories with git and Pub.
If you're planning on using Melos in your GitHub Actions workflows, you can use the Melos Action to run Melos commands, this action also supports automatic versioning and publishing directly from your workflows.
A default file structure looks something like this:
my-melos-repo/
melos.yaml
packages/
package-1/
pubspec.yaml
package-2/
pubspec.yaml
The location of your packages can be configured via the melos.yaml
configuration file if the default is unsuitable.
- 🔗 Link local packages in your workspace together without adding dependency overrides.
- 📦 Automatically version, create changelogs and publish your packages using Conventional Commits.
- 📜 Pre-define advanced custom scripts for your workspace in your
melos.yamlconfiguration to use viamelos run [scriptName]. Anyone contributing to your workspace can just runmelos runto be prompted to select a script from a list with descriptions of each script.- Scripts can even prompt to select a package to run against with pre-defined filters.
- ⚡ Execute commands across your packages easily with
melos exec -- <command here>with additional concurrency and fail-fast options.- Environment variables containing various information about the current package and the workspace are available in each execution.
- Can be combined with all package filters.
- 🎯 Many advanced package filtering options allowing you to target specific
packages or groups of packages in your workspace.
--no-private- Exclude private packages (
publish_to: none).
- Exclude private packages (
--[no-]published- Filter packages where the current local package version exists on pub.dev. Or "-no-published" to filter packages that have not had their current version published yet.
--[no-]nullsafety- Filter packages where the current local version uses a "nullsafety" prerelease preid. Or "-no-nullsafety" to filter packages where their current version does not have a "nullsafety" preid.
--[no-]flutter- Filter packages where the package depends on the Flutter SDK. Or "-no-flutter" to filter packages that do not depend on the Flutter SDK.
--scope=<glob>- Include only packages with names matching the given glob.
--ignore=<glob>- Exclude packages with names matching the given glob.
--diff=<ref>- Only include packages that have been changed since the specified
ref, e.g. a commit sha or git tag.
- Only include packages that have been changed since the specified
--dir-exists=<dirRelativeToPackageRoot>- Include only packages where a specific directory exists inside the package.
--file-exists=<fileRelativeToPackageRoot>- Include only packages where a specific file exists in the package.
--depends-on=<dependantPackageName>- Include only packages that depend on a specific package.
--no-depends-on=<noDependantPackageName>- Include only packages that don't depend on a specific package.
--include-dependencies- Expands the filtered list of packages to include those packages' transitive dependencies (ignoring filters).
--include-dependents- Expands the filtered list of packages to include those packages' transitive dependents (ignoring filters).
- ♨️ Advanced support for IntelliJ IDEs with automatic creation of
run configurations for workspace defined scripts and more
on workspace bootstrap.
- Integration with VS Code through an extension.
Go to the Getting Started page of the documentation to start using Melos.
The following projects are using Melos:
- firebase/flutterfire
- Flame-Engine/Flame
- fluttercommunity/plus_plugins
- GetStream/stream-chat-flutter
- 4itworks/opensource_qwkin_dart
- gql-dart/ferry
- cbl-dart/cbl-dart
- ema987/paddinger
- flutter-stripe/flutter_stripe
- danvick/flutter_form_builder
- kmartins/groveman
- flutternetwork/WiFiFlutter
- iapicca/yak_packages
- atsign-foundation/at_app
- sub6resources/flutter_html
- ferraridamiano/ConverterNOW
- rrifafauzikomara/youtube_video
- mobxjs/mobx.dart
- NetGlade/auto_mappr
- myConsciousness/atproto.dart
- GrowERP Flutter ERP
- mrverdant13/coverde
- ThexXTURBOXx/flutter_web_auth_2
- woltapp/wolt_modal_sheet
- cfug/dio
- simolus3/drift
- Lyokone/flutterlocation
- FlutterGen/flutter_gen
- canonical/ubuntu-desktop-provision
- ubuntu/app-center
- jhomlala/alice
- powersync/powersync.dart
- rodydavis/signals.dart
- foss42/apidash
Submit a PR if you'd like to add your project to the list. Update the README.md and the docs.
You can also add a README badge to your projects README to let others know about Melos 💙.
Documentation is available at https://melos.invertase.dev.
When migrating between major versions of Melos, please read the migration guide.
Full commands list and args can be viewed by running melos --help.
> melos --help
A CLI tool for managing Dart & Flutter projects with multiple packages.
Usage: melos <command> [arguments]
Global options:
-h, --help Print this usage information.
--verbose Enable verbose logging.
--sdk-path Path to the Dart/Flutter SDK that should be used. This command line option has
precedence over the `sdkPath` option in the `melos.yaml` configuration file and the
`MELOS_SDK_PATH` environment variable. To use the system-wide SDK, provide the
special value "auto".
Available commands:
analyze Analyzes all packages in your project for potential issues in a single run. Optionally
configure severity levels. Supports all package filtering options.
bootstrap Initialize the workspace, link local packages together and install remaining package
dependencies. Supports all package filtering options.
clean Clean this workspace and all packages. This deletes the temporary pub & ide files such
as ".packages" & ".flutter-plugins". Supports all package filtering options.
exec Execute an arbitrary command in each package. Supports all package filtering options.
format Idiomatically format Dart source code.
list List local packages in various output formats. Supports all package filtering options.
publish Publish any unpublished packages or package versions in your repository to pub.dev. Dry
run is on by default.
run Run a script by name defined in the workspace melos.yaml config file.
version Automatically version and generate changelogs based on the Conventional Commits
specification. Supports all package filtering options.
Run "melos help <command>" for more information about a command.
To start making contributions please refer to
CONTRIBUTING.md.
This project is heavily inspired by Lerna.
Using Melos? Add a README badge to show it off:
[](https://github.com/invertase/melos)- See LICENSE
Built and maintained with 💛 by Invertase.
