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Buildpack Deployment


Subcommands introduced in 0.15.0

buildpacks:add [--index 1] <app> <buildpack>  # Add new app buildpack while inserting into list of buildpacks if necessary
buildpacks:clear <app>                        # Clear all buildpacks set on the app
buildpacks:list <app>                         # List all buildpacks for an app
buildpacks:remove <app> <buildpack>           # Remove a buildpack set on the app
buildpacks:report [<app>] [<flag>]            # Displays a buildpack report for one or more apps
buildpacks:set [--index 1] <app> <buildpack>  # Set new app buildpack at a given position defaulting to the first buildpack if no index is specified


If using the buildpacks plugin, be sure to unset any BUILDPACK_URL and remove any such entries from a committed .env file. A specified BUILDPACK_URL will always override a .buildpacks file or the buildpacks plugin.

Dokku normally defaults to using Heroku buildpacks for deployment, though this may be overridden by committing a valid Dockerfile to the root of your repository and pushing the repository to your Dokku installation. To avoid this automatic Dockerfile deployment detection, you may do one of the following:

  • Set a BUILDPACK_URL environment variable
  • This can be done via dokku config:set or via a committed .env file in the root of the repository. See the environment variable documentation for more details.
  • Create a .buildpacks file in the root of your repository.
  • This can be via a committed .buildpacks file or managed via the buildpacks plugin commands.

This page will cover usage of the buildpacks plugin.


Listing Buildpacks in Use

The buildpacks:list command can be used to show buildpacks that have been set for an app. This will omit any auto-detected buildpacks.

# running for an app with no buildpacks specified
dokku buildpacks:list node-js-app
-----> test buildpack urls
# running for an app with two buildpacks specified
dokku buildpacks:list node-js-app
-----> test buildpack urls

Adding custom buildpacks


Please check the documentation for your particular buildpack as you may need to include configuration files (such as a Procfile) in your project root.

To add a custom buildpack, use the buildpacks:add command:

dokku buildpacks:add node-js-app

When no buildpacks are currently specified, the specified buildpack will be the only one executed for detection and compilation.

Multiple buildpacks may be specified by using the buildpacks:add command multiple times.

dokku buildpacks:add node-js-app
dokku buildpacks:add node-js-app

Buildpacks are executed in order, may be inserted at a specified index via the --index flag. This flag is specified starting at a 1-index value.

# will add the golang buildpack at the second position, bumping all proceeding ones by 1 position
dokku buildpacks:add --index 2 node-js-app

Overwriting a buildpack position

In some cases, it may be necessary to swap out a given buildpack. Rather than needing to re-specify each buildpack, the buildpacks:set command can be used to overwrite a buildpack at a given position.

dokku buildpacks:set node-js-app

By default, this will overwrite the first buildpack specified. To specify an index, the --index flag may be used. This flag is specified starting at a 1-index value, and defaults to 1.

# the following are equivalent commands
dokku buildpacks:set node-js-app
dokku buildpacks:set --index 1 node-js-app

If the index specified is larger than the number of buildpacks currently configured, the buildpack will be appended to the end of the list.

dokku buildpacks:set --index 99 node-js-app

Removing a buildpack


At least one of a buildpack or index must be specified

A single buildpack can be removed by name via the buildpacks:remove command.

dokku buildpacks:remove node-js-app

Buildpacks can also be removed by index via the --index flag. This flag is specified starting at a 1-index value.

dokku buildpacks:remove node-js-app --index 1

Clearing all buildpacks


This does not affect automatically detected buildpacks, nor does it impact any specified BUILDPACK_URL environment variable.

The buildpacks:clear command can be used to clear all configured buildpacks for a specified app.

dokku buildpacks:clear node-js-app

Displaying buildpack reports for an app

You can get a report about the app's buildpacks status using the buildpacks:report command:

dokku buildpacks:report
=====> node-js-app buildpacks information
       Buildpacks list:     
=====> python-sample buildpacks information
       Buildpacks list:     ,
=====> ruby-sample buildpacks information
       Buildpacks list:

You can run the command for a specific app also.

dokku buildpacks:report node-js-app
=====> node-js-app buildpacks information
       Buildpacks list:     

You can pass flags which will output only the value of the specific information you want. For example:

dokku buildpacks:report node-js-app --buildpacks-list


Switching from Dockerfile deployments

If an application was previously deployed via Dockerfile, the following commands should be run before a buildpack deploy will succeed:


Using a specific buildpack version


Always remember to pin your buildpack versions when using the multi-buildpacks method, or you may find deploys changing your deployed environment.

By default, Dokku uses the gliderlabs/herokuish project, which pins all of it's vendored buildpacks. There may be occasions where the pinned version results in a broken deploy, or does not have a particular feature that is required to build your project. To use a more recent version of a given buildpack, the buildpack may be specified without a Git commit SHA like so:

# using the latest nodejs buildpack
dokku buildpacks:set node-js-app

This will use the latest commit on the master branch of the specified buildpack. To pin to a newer version of a buildpack, a sha may also be specified by using the form REPOSITORY_URL#COMMIT_SHA, where COMMIT_SHA is any tree-ish git object - usually a git tag.

# using v87 of the nodejs buildpack
dokku buildpacks:set node-js-app

Specifying commands via Procfile

While many buildpacks have a default command that is run when a detected repository is pushed, it is possible to override this command via a Procfile. A Procfile can also be used to specify multiple commands, each of which is subject to process scaling. See the process scaling documentation for more details around scaling individual processes.

A Procfile is a file named Procfile. It should be named Procfile exactly, and not anything else. For example, Procfile.txt is not valid. The file should be a simple text file.

The file must be placed in the root directory of your application. It will not function if placed in a subdirectory.

If the file exists, it should not be empty, as doing so may result in a failed deploy.

The syntax for declaring a Procfile is as follows. Note that the format is one process type per line, with no duplicate process types.

<process type>: <command>

If, for example, you have multiple queue workers and wish to scale them separately, the following would be a valid way to work around the requirement of not duplicating process types:

worker:           env QUEUE=* bundle exec rake resque:work
importantworker:  env QUEUE=important bundle exec rake resque:work

The web process type holds some significance in that it is the only process type that is automatically scaled to 1 on the initial application deploy. See the process scaling documentation for more details around scaling individual processes.

curl build timeouts

Certain buildpacks may time out in retrieving dependencies via curl. This can happen when your network connection is poor or if there is significant network congestion. You may see a message similar to gzip: stdin: unexpected end of file after a curl command.

If you see output similar this when deploying , you may need to override the curl timeouts to increase the length of time allotted to those tasks. You can do so via the config plugin:

dokku config:set --global CURL_TIMEOUT=1200
dokku config:set --global CURL_CONNECT_TIMEOUT=180

Clearing buildpack cache

See the repository management documentation.