Build extensions allow you to hook into the build system and customize the build process or the resulting bundle and container image (in the case of deploying). You can use pre-built extensions by installing the @trigger.dev/build package into your devDependencies, or you can create your own. Build extensions are added to your trigger.config.ts file under the build.extensions property: 
import { defineConfig } from "@trigger.dev/sdk/v3";

export default defineConfig({
  project: "my-project",
  build: {
    extensions: [
      {
        name: "my-extension",
        onBuildStart: async (context) => {
          console.log("Build starting!");
        },
      },
    ],
  },
});
If you are using a pre-built extension, you can import it from the @trigger.dev/build package: 
import { defineConfig } from "@trigger.dev/sdk/v3";
import { ffmpeg } from "@trigger.dev/build/extensions/core";

export default defineConfig({
  project: "my-project",
  build: {
    extensions: [ffmpeg()],
  },
});

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Built-in extensions

Trigger.dev provides a set of built-in extensions that you can use to customize how your project is built and deployed. These extensions are available out of the box and can be configured in your trigger.config.ts file.
ExtensionDescription
prismaExtensionUsing prisma in your Trigger.dev tasks
pythonExtensionExecute Python scripts in your project
playwrightUse Playwright in your Trigger.dev tasks
puppeteerUse Puppeteer in your Trigger.dev tasks
ffmpegUse FFmpeg in your Trigger.dev tasks
aptGetInstall system packages in your build image
additionalFilesCopy additional files to your build image
additionalPackagesInstall additional npm packages in your build image
syncEnvVarsAutomatically sync environment variables from external services to Trigger.dev
syncVercelEnvVarsAutomatically sync environment variables from Vercel to Trigger.dev
esbuildPluginAdd existing or custom esbuild extensions to customize your build process
emitDecoratorMetadataEnable emitDecoratorMetadata in your TypeScript build
audioWaveformAdd Audio Waveform to your build image

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Custom extensions

If one of the built-in extensions doesn’t meet your needs, you can create your own custom extension. See our guide on creating custom build extensions for more information.