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* docs: add archive note to the README

* chore: update link

* Add updated docs link

Co-authored-by: jmarlena <>

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December 6, 2018 17:57
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Netlify Build Image

Archive note

We have archived this repository and moved the code to a private repository. This decision was made to provide shorter development cycles and allow us to react faster on issues.

Sadly, this change comes with the bittersweet price of not having this repository open source anymore.

We apologize for this inconvenience and still want to hear from you on issues you encounter or feature requests.

To support your troubleshooting, we will still publish the build-image to Docker Hub for now. We would love to make troubleshooting easier for you, but first we need to understand your unique situation.

Since we would love to understand the troubleshooting issues you’re encountering, we kindly ask you to reach out to our Support team in the Forums. Again, we would love to make troubleshooting easier for you, but first we need to understand your unique situation.

How to report features and bugs?

To build a better web, we still need your valuable input and feedback! Help us build a better web by reporting issues or proposing feature requests to our build system through our Support Forum.

Find out which software & version is available inside your builds

We updated our documentation page to reflect an accurate list of all the languages and software that is currently available in our builds.

You can check it out at our docs page.

This repository contains the tools to make the build image that Netlify's continuous deployment buildbot uses to build a site from a connected Git repository.

If you're having problems with your build, you can also use these tools to test locally.

Available images

Netlify maintains multiple build images for testing new development as well as supporting legacy builds. Each image uses a different version of Ubuntu Linux, with a slightly different list of included language and software versions.

The following image is currently available:

  • focal - Default build image for all new sites; Running Ubuntu 20.04 and this software

Each image name above corresponds to a branch in this repository.

Running locally

Emulating Netlify's buildbot on your local machine requires the following:

  • Docker
  • A local clone of this build-image repository
  • A local clone of the site repository you want to test, checked out to the branch you want to be built, with a clean git status (nothing to commit).

Step 1: Pull the build image

Open your Docker terminal, and run the following command to pull the default image:

docker pull netlify/build:focal
docker pull netlify/build:v3.0.2 # replace the version with a git tag of the specific version you want to test

Step 2: Start the script to run interactively

Still in your Docker terminal, change directories into your local clone of this build-image repository.

If you pulled an alternate image in Step 1, check out the corresponding branch in this repository.

Run the following command to start the interactive shell within the container:

./test-tools/ path/to/site/repo

If you receive a command not found message, make sure you are in the base of the build-image repository.

If the command works correctly, you should see a new prompt, with the user buildbot.

Step 3: Have the buildbot run your build command

In the buildbot shell, run build followed by your site build command. For example, for a site build command of npm run build, you would run the following:

/opt/build-bin/build npm run build

This will run the build as it would run on Netlify, displaying logs in your terminal as it goes. When you are done testing, you can exit the buildbot shell by typing exit.

Build environment variables

Your local buildbot emulator doesn't have access to build environment variables set in the Netlify UI or netlify.toml file. However, you can explicitly set them in the interactive buildbot shell before running your build command.

Here is an example that sets NODE_VERSION and NODE_ENV before running a build command of npm run build:

export NODE_VERSION=8 NODE_ENV=production ; build npm run build

Testing it for a mono repository

If you like to run a debugging build for your mono repository you need to pass the Base directory like in the Netlify UI.

./test-tools/ path/to/site/repo base/directory 'your build command'

Testing locally with cache

If you'd like to run a debugging build using our caching mechanisms, with verbose shell output, you can replace steps 2 and 3 above with the following command:

./test-tools/ path/to/site/repo 'your build command'

This will create a tmp directory that will have the repo that the buildbot cloned, the scripts run by the buildbot, and the cache (with hidden files). The terminal displays the path to the tmp directory at the start of each build. You specify this path in an environment variable prepended to the command above, like so:

T=tmp/tmp.XXXXX ./test-tools/ path/to/site/repo 'your build command'


Visit the development section in our


Pull requests welcome, as long as they're not overly specific to a niche use-case.

Please see our contributing documentation.

More info

How we use this and some best practices are documented here: