Serverless Esbuild

Serverless plugin to bundle JavaScript and TypeScript lambdas with esbuild - an extremely fast bundler and minifier

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💨 serverless-esbuild

Serverless plugin for zero-config JavaScript and TypeScript code bundling using promising fast & furious esbuild bundler and minifier

serverless npm version npm downloads build status semantic-release


  • Zero-config: Works out of the box without the need to install any additional plugins
  • Works with Typescript and Javascript projects
  • Supports sls package, sls deploy, sls deploy function
  • Integrates with Serverless Invoke Local & serverless-offline

Table of Contents


# install `serverless-esbuild` and `esbuild`
yarn add --dev serverless-esbuild esbuild
# or
npm install -D serverless-esbuild esbuild
# or
pnpm install -D serverless-esbuild esbuild

Add the following plugin to your serverless.yml:

  - serverless-esbuild


By default, no configuration is required, but you can override the default behavior via the custom.esbuild section in the serverless.yml file.

    bundle: true
    minify: false


See example folder for some example configurations.


Option Description Default
Esbuild Options This plugin can take almost any Esbuild Javascript Build Option. See Default Esbuild Options N/A
concurrency The number of concurrent zip and bundle operations to run at once (This can be memory intensive). eg. 10. NOTE: This will produce slower builds. 'Infinity'
disableIncremental Disables the use of esbuild incremental compilation. false
exclude An array of dependencies to exclude from the Lambda. This is passed to the esbuild external option. Set to * to disable packaging node_modules ['aws-sdk']
installExtraArgs Optional arguments passed to npm or yarn for external dependency resolution. eg. ['--legacy-peer-deps'] for npm v7+ to use legacy peerDependency resolution behavior []
keepOutputDirectory Keeps the .esbuild output folder. Useful for debugging. false
nativeZip Uses the system's zip executable to create archives. NOTE: This will produce non-deterministic archives which causes a Serverless deployment update on every deploy. false
packagePath Path to the package.json file for external dependency resolution. './package.json'
packager Package to use for external dependency resolution. Values: npm, yarn, pnpm 'npm'
packagerOptions Extra options for packagers for external dependency resolution. See Packager Options N/A
watch Watch options for serverless-offline. See Watch Options N/A

Default Esbuild Options

The following esbuild options are automatically set.

Option Default Notes
bundle true Esbuild requires this for use with external
entryPoints N/A Cannot be overridden
incremental N/A Cannot be overridden. Use disableIncremental to disable it
outDir N/A Cannot be overridden
platform 'node' Set to 'neutral' to enable ESM support
target 'node12' We dynamically set this. See Supported Runtimes

Packager Options

Option Description Default
scripts A string or array of scripts to be executed, currently only supports 'scripts' for npm, pnpm and yarn undefined

Watch Options

Option Description Default
pattern An anymatch-compatible definition for the watcher to respond to ./\*_/_.(js|ts) (watches all .js and .ts files)
ignore An anymatch-compatible definition for the watcher to ignore ['.build', 'dist', 'node_modules', '.serverless']

Supported Runtimes

This plugin will automatically set the esbuild target for the following supported Serverless runtimes


Runtime Target
nodejs14.x node14
nodejs12.x node12

If you wish to use this plugin alongside non Node functions like Python or functions with images, this plugin will automatically ignore any function which does not contain a handler or use a supported Node.js runtime.

Advanced Configuration

Including Extra Files

Serverless Package Configuration will behave in the same way as native packaging. You can use patterns, include and exclude to include extra files into your bundles.

External Dependencies

Packages that are marked as external and exist in the package.json's dependencies will be installed and included with your build under node_modules. You can customize this with a number of options.

      - lodash
    packager: yarn
    packagePath: absolute/path/to/package.json
        - echo 'Hello World!'
        - rm -rf node_modules
      - '--legacy-peer-deps'

To easily mark all the dependencies in package.json as external, you can utilize esbuild-node-externals plugin.

To mark one or more individual packages as external, use the following configuration:

      - 'my-package-name'
      - 'another-package-name'

Esbuild Plugins

Note: The Esbuild plugins API is still experimental

You can configure esbuild plugins by passing a plugins' configuration file:

    plugins: plugins.js

The plugins' configuration file must be a javascript file exporting an array of plugins (see examples/individually/plugins.js for a dummy plugin example):

let myPlugin = {
  name: 'my-plugin',
  setup(build) {
    // plugin implementation

// default export should be an array of plugins
module.exports = [myPlugin];

or a function that accepts serverless instance and returns an array of plugins (see issue #168 for an example):

module.exports = (serverless) => {
  const myPlugin = {
    name: 'my-plugin',
    setup(build) {
      // plugin implementation with `serverless` instance access
      console.log('sls custom options', serverless.service.custom);

  // an array of plugins must be returned
  return [myPlugin];


Automatic compilation

As long as the plugin is properly installed, all regular Serverless operations sls package, sls deploy, sls deploy function, sls invoke local, sls offline will automatically compile using serverless-esbuild.

Serverless Offline

The plugin integrates very well with serverless-offline to simulate AWS Lambda and AWS API Gateway locally.

Add the plugins to your serverless.yml file and make sure that serverless-esbuild precedes serverless-offline as the order is important:

plugins: ...
  - serverless-esbuild
  - serverless-offline

Run serverless offline or serverless offline start to start the Lambda/API simulation.

In comparison to serverless offline, the start command will fire an init and a end lifecycle hook which is needed for serverless-offline and e.g. serverless-dynamodb-local to switch off resources (see below)

Automatic compilation is available while using the plugin with serverless-offline.

      pattern: ['src/**/*.ts'] # match only typescript files in src directory
      ignore: ['temp/**/*']

Note: When overriding the ignore pattern, remember to ignore .build directory to avoid endless compilation.

Serverless Dynamodb Local

Configure your service the same as mentioned above, but additionally add the serverless-dynamodb-local plugin as follows:

  - serverless-esbuild
  - serverless-dynamodb-local
  - serverless-offline

Run serverless offline start.

Invoke Local

This plugin supports the Serverless Invoke Local functionality and will automatically compile the selected function.

External Tools


Most active, having Collaborator role:

@floydspace @olup @samchungy @vamche

Inspired by serverless-plugin-typescript and serverless-webpack