Dockerfile Build Pack | Coolify Docs

Dockerfile includes step-by-step instructions to build a Docker image that Coolify uses to deploy your application or website.

The Dockerfile build pack allows you to use your own Dockerfile to deploy your application, you have complete control over how your application is built and deployed on Coolify.

How to use Dockerfile?

1. Create a New Resource in Coolify

On the Coolify dashboard, open your project and click the Create New Resource button.

2. Choose Your Deployment Option

A. If your Git repository is public, choose the Public Repository option.

B. If your repository is private, you can select Github App or Deploy Key. (These methods require extra configuration. You can check the guides on setting up a Github App or Deploy Key if needed.)

3. Select Your Git Repository

If you are using a public repository, paste the URL of your GitHub repository when prompted. The steps are very similar for all other options.

4. Choose the Build Pack

Coolify defaults to using Nixpacks. Click the Nixpacks option and select Dockerfile as your build pack from the dropdown menu.

5. Configure the Build Pack

Branch: Coolify will automatically detect the branch in your repository.
Base Directory: Enter the directory that Coolify should use as the root. Use / if your files are at the root or specify a subfolder (like /backend for a monorepo).

Click on Continue button once you have set all the above settings to correct details.

6. Configure Network Settings

After clicking Continue, update settings like your domain and environment variables (if needed).

The important option is the port where your application runs. Coolify sets the default port to 3000, so if your application listens on a different port, update the port number on the network section.

Advanced Configuration

Environment Variables

You can manage your environment variables from the Coolify UI.

Click on the Environment Variables tab to add or update them.

Pre/Post Deployment Commands

Pre-deployment: Optionally, specify a script or command to execute in the existing container before deployment begins. This command is run with sh -c, so you do not need to add it manually.
Post-deployment: Optionally, specify a script or command to execute in the newly built container after deployment completes. This command is also executed with sh -c.

Build Arguments

Coolify automatically injects build arguments into your Dockerfile during the build process. These include environment variables you've configured and predefined system values like SOURCE_COMMIT.

You can configure these settings in the Advanced menu of your application.

Inject Build Args to Dockerfile

By default, Coolify injects Docker build arguments (ARG statements) into your Dockerfile. If you prefer to manage build arguments manually in your Dockerfile, you can disable this behavior in the Advanced menu.

Enabled (default): Coolify automatically injects build arguments
Disabled: You manage ARG statements yourself in the Dockerfile

Include Source Commit in Build

The SOURCE_COMMIT variable contains the Git commit hash of your source code. By default, this is excluded from the build to preserve Docker's build cache. You can enable this in the Advanced menu if needed.

Disabled (default): SOURCE_COMMIT is not included, improving cache utilization
Enabled: SOURCE_COMMIT is included as a build argument

Build Cache Optimization

Enabling "Include Source Commit in Build" will cause Docker's build cache to be invalidated on every commit, since the commit hash changes each time. Only enable this if your build process requires the commit hash.

Node.js Multi-Core Scaling

A plain Node.js process only uses one CPU core. To make a Node.js (or Bun) app use every core on the host from a single Dockerfile build, see the Node.js Multi-Core Scaling guide.