The complexity of applications has changed dramatically over the last decade, and nowadays it is not always straightforward to contribute to a new project for the first time. At the beginning, developers need to properly set up the local environment including:

  • build tools

  • runtimes

  • dependencies

  • IDEs

For complex projects, it could easily take weeks for new developers to get the builds running on their machines. In general, a significant amount of the team’s week is spent on building and maintaining developer environments. With Eclipse Che we are solving the complexity of the onboarding, configuration, and setup by defining a new cloud-native, zero-install, and repeatable concept of a workspace.

Contributing for the first time to a project using Eclipse Che

The motto of Eclipse Che is that anyone anytime can contribute to a project without installing software. In order to contribute to a project, just click on the badge defined in the file of the repository, and within a minute you will get a workspace ready for development with all the tools and runtimes available out of the box.

Contribute Badge
Figure 1. The Eclipse Che contribute badge in

By default, Eclipse Che is using a customized version of Theia, which provides VS Code-like experience including the support of extensions:

Eclipse Che Theia IDE
Figure 2. Eclipse Che Theia IDE

Programming languages facilities like code completion, navigation, and CodeLens are provided using the Language Server Protocol. Eclipse Che benefits from a growing ecosystem of over 60 available language servers, delivering intelligent editing support for all major programming languages.

Content Assist
Figure 3. Java Content Assist

Pre-defined commands (TerminalRun Task…​) allow you to easily build, run, debug, and test the application.

IDE Commands
Figure 4. Pre-defined commands

Additional extensions can be enabled by using the Ctrl+Shift+J shortcut or ViewPlugins menu items:

The 'Plugins' view
Figure 5. The 'Plugins' view

Debug the application by using the F5 shortcut or RunStart Debugging menu items:

Debugging the application
Figure 6. Debugging Java application

Commit and push the changes from the terminal or use the Source Control view:

[The 'Source Control' view
Figure 7. The 'Source Control' view

Now you are ready for the first contribution. For GitHub, a dedicated plugin is available that allows opening pull requests right from the IDE:

[The 'GitHub' plugin
Figure 8. The 'GitHub' plugin

How can maintainers set up their projects to use Eclipse Che?

At the moment, Eclipse Che hosted by Red Hat does not use the DevWorkspace Operator that is in charge of the devfile v2 support. The switch to the DevWorkspace engine is planned for spring 2022. Currently, devfiles v2 are automatically converted to devfile v1 equivalents via the converter library under the hood during workspace startup.
The recommended file structure of the repository
  |--- devfile.yaml
  |___ .che
         |___ che-editor.yaml
         |___ che-theia-plugins.yaml
  |___ .vscode
         |___ extensions.json
         |___ launch.json
  • Add .devfile.yaml or devfile.yaml file to the root of the project in order to specify the relevant components and commands in a declarative way.

The devfile provides easy to configure, highly reproducible definitions of portable developer environments. For more information about devfiles, see the Devfile Documentation.

Omitting the creation of the devfile file will result in using a default container based on the Universal Developer Image, which provides various languages (including Java, Node.js, Python, PHP, Golang, etc) and tools (including curl, jq, git, etc).
  • Add the .vscode/extensions.json file to the root of the project in order to add VS Code extensions if the editor is Theia (the default) or VS Code:

  "recommendations": [
The list of VS Code extensions is available in the Eclipse Che plug-in registry. If the specified extensions are not available in the registry, the workspace will start, but the extensions will not be added to the workspace.
  • Add the .vscode/launch.json file for specifying Run and Debug commands if the editor is Theia or VS Code:

    "version": "0.2.0",
    "configurations": [
            "type": "java",
            "name": "Debug (Attach) - Remote",
            "request": "attach",
            "hostName": "localhost",
            "port": 5005
  • Add the .che/che-theia-plugins.yaml file if extra customizations of Theia plugins are required.

Eclipse Che uses .che/che-theia-plugins.yaml file only if the editor is Theia.

For example, overriding the default memory limit of sidecar container:

- id: redhat/java
      memoryLimit: 2Gi
  • Add the .che/che-editor.yaml file to override the default editor (Theia) with a different one (e.g. VS Code or JetBrains IntelliJ) and specify the editor container properties. For example, overriding the default memory limit of the theia-ide container:

id: eclipse/che-theia/latest          # mandatory
registryUrl:  # optional
override:                             # optional
    - name: theia-ide
      memoryLimit: 1280Mi
  • Add the Eclipse Che badge to the project file with a link for starting a workspace:

Contribute Badge
Figure 9. The official Eclipse Che badge


Once the line above is added to the, it will be possible to start a workspace by simply clicking on the badge icon.

Eclipse Che images from Simple Icons can be also used for generation of the custom badges via Shields IO.
Contribute Badge
Contribute Badge
Contribute Badge
Contribute Badge
Contribute Badge

Now you are all set. Happy Coding!