The JS plugin contains executors and generators that are useful for JavaScript/TypeScript projects in an Nx workspace.
Setting Up @nx/js
Installation
Make sure to install the @nx/js version that matches the version of nx in your repository. If the version numbers get out of sync, you can encounter some difficult to debug errors. You can fix Nx version mismatches with this recipe.
In any Nx workspace, you can install @nx/js by running the following command:
❯
nx add @nx/js
This will install the correct version of @nx/js.
ts Preset
When initializing a new Nx workspace, specifying --preset=ts will generate a workspace with @nx/js pre-installed.
❯
npx create-nx-workspace my-org --preset=ts
Nx 20 updates the TS monorepo setup when using --preset=ts. The workspace is set up with TypeScript Project References along with the Workspaces feature from npm, yarn, pnpm, and bun.
To create with the older setup for TS monorepo with compilerOptions.paths, use create-nx-workspace --preset=apps.
How @nx/js Infers Tasks
The @nx/js/typescript plugin will add a typecheck task to projects that have a tsconfig.json.
This plugin adds a build task for projects that:
- Have a runtime tsconfig file (defaults to
tsconfig.lib.json). - Have a
package.jsonfile containing entry points that are not source files.
For example, this project is buildable and will have a build task.
1{
2 "name": "@acme/pkg1",
3 "exports": {
4 "./package.json": "./package.json",
5 ".": {
6 "types": "./dist/index.d.ts",
7 "default": "./dist/index.js"
8 }
9 }
10}
11Whereas this project points to source files and will not have a build task.
1{
2 "name": "@acme/pkg1",
3 "exports": {
4 "./package.json": "./package.json",
5 ".": "./src/index.ts"
6 }
7}
8View Inferred Tasks
To view inferred tasks for a project, open the project details view in Nx Console or run nx show project my-project in the command line.
@nx/js Configuration
The @nx/js/typescript plugin is configured in the plugins array in nx.json.
1{
2 "plugins": [
3 {
4 "plugin": "@nx/js/typescript",
5 "options": {
6 "typecheck": {
7 "targetName": "typecheck"
8 },
9 "build": {
10 "targetName": "build",
11 "configName": "tsconfig.lib.json"
12 }
13 }
14 }
15 ]
16}
17You can also set typecheck and build options to false to not infer the corresponding tasks.
1{
2 "plugins": [
3 {
4 "plugin": "@nx/js/typescript",
5 "options": {
6 "build": false
7 }
8 }
9 ]
10}
11Disable Typechecking
To disable typecheck task for a specific project, set the nx.addTypecheckTarget property to false in tsconfig.json.
1{
2 "extends": "../../tsconfig.base.json",
3 "files": [],
4 "include": [],
5 "references": [
6 {
7 "path": "./tsconfig.lib.json"
8 }
9 ],
10 "nx": {
11 "addTypecheckTarget": false
12 }
13}
14Create Libraries
You can add a new JS/TS library with the following command:
❯
nx g @nx/js:lib libs/my-lib
Build
You can build libraries that are generated with a bundler specified.
❯
nx g @nx/js:lib libs/my-buildable-lib --bundler=rollup
Generating a library with --bundler specified will add a build target to the library's project.json file allows the library to be built.
❯
nx build my-buildable-lib
Test
You can test a library with the following command:
❯
nx test my-lib
Lint
You can lint a library with the following command:
❯
nx lint my-lib
Compiler
By default, @nx/js uses TypeScript Compiler (TSC), via @nx/js:tsc executor, to compile your libraries. Optionally, you can switch tsc out for a different compiler with --compiler flag when executing the generators.
Currently, @nx/js supports the following compilers:
SWC
- Create a buildable library with
swc
❯
nx g @nx/js:lib libs/my-swc-lib --bundler=swc
- Convert a
tsclibrary to useswc
❯
nx g @nx/js:convert-to-swc my-buildable-lib
Now the build command will use @nx/js:swc executor to compile your libraries.
The first time you generate a
swclibrary or convert atsclibrary over toswc,@nx/jswill install the necessary dependencies to useswc.