Automate Updating Dependencies
Keeping a codebase updated with the latest changes in your framework of choice can be challenging. Not to mention that "tooling maintenance work" is usually hard to squeeze into your feature sprint.
nx migrate command helps by automating the process of updating:
- package versions in your
- configuration files (e.g. your Jest, ESLint or Nx config)
- your source code (e.g. fixing breaking changes or migrating to new best practices)
How does it work?
Nx knows where its configuration files are and can therefore make sure they match the expected format. This automated update process, commonly referred to as "migration," becomes even more powerful when you leverage Nx plugins. Nx plugins, which are NPM packages with a range of capabilities (code generation, task automation...), offer targeted updates based on their specific areas of responsibility.
For example, the Nx ESLint plugin excels at configuring linting in your workspace. With its understanding of the configuration file locations, this plugin can provide precise migration scripts to update ESLint packages in your
package.json and corresponding configuration files in your workspace when a new version is released.
Updating happens in three steps:
- The installed dependencies are updated including the
- The source code in the repo is updated to match the new versions of packages according to the set of instructions specified in
- Optionally remove the
migrations.jsonfile or keep it to re-run the migration in different Git branches
Step 1: Updating dependencies and generating migrations
First, run the
nx migrate latest # same as nx migrate nx@latest
Note you can also specify an exact version by replacing
This fetches the specified version of the
nx package, analyzes the dependencies and fetches all the dependent packages. The process keeps going until all the dependencies are resolved. This results in:
migrations.jsonbeing generated if there are pending migrations.
At this point, no packages have been installed, and no other files have been touched.
Now, you can inspect
package.json to see if the changes make sense. Sometimes the migration can update a package to a version that is either not allowed or conflicts with another package. Feel free to manually apply the desired adjustments.
At this stage, after inspecting the
package.json, you may wish to manually run the appropriate install command for your workspace (e.g.
pnpm install) but in the next step
nx migrate --run-migrations will also run this automatically for you.
Step 2: Running migrations
You can now run the actual code migrations that were generated in the
migrations.json in the previous step.
nx migrate --run-migrations
This will update your source code in your workspace in accordance with the implementation of the various migrations which ran and all the changes will be unstaged ready for you to review and commit yourself.
Note that each Nx plugin is able to provide a set of migrations which are relevant to particular versions of the package. Hence
migrations.json will only contain migrations which are appropriate for the update you are currently applying.
Step 3: Cleaning up
After you run all the migrations, you can remove
migrations.json and commit any outstanding changes.
Note: You may want to keep the
migrations.json until every branch that was created before the migration has been merged. Leaving the
migrations.json in place allows devs to run
nx migrate --run-migrations to apply the same migration process to their newly merged code as well.
Keep Nx Packages on the Same Version
When you run
nx migrate, the
nx package and all the
@nx/ packages get updated to the same version. It is important to keep these versions in sync, or you can encounter some difficult to debug errors. As long as you run
nx migrate instead of manually changing the version numbers, you shouldn't have to worry about it. Also, when you add a new plugin, use
nx add <plugin> to automatically install the version that matches your repository's version of Nx.
nx-cloud package does not need to be in sync with the other Nx packages. For best results, stay on the latest version of
nx-cloud. The latest
nx-cloud version supports the most recent 2 major versions of
nx, although earlier versions of
nx may also be compatible.
Migrate Community Plugins Individually
Community plugins should be migrated individually with:
nx migrate my-plugin
For a list of all the plugins you currently have installed, run:
Need to opt-out of some migrations?
Sometimes you need to temporarily opt-out from some migrations because your workspace is not ready yet. You can manually adjust the
migrations.json or run the update with the
--interactive flag to choose which migrations you accept. Find more details in our Advanced Update Process guide.