---
url: /en/workspaces/custom-dev-pipeline.md
---
If you want to use a custom pipeline configuration when clicking the `Workspaces` button on the branch page, you can add a `.cnb.yml` file in the repository root directory with the following configuration:

```yaml title=".cnb.yml"
$:
  # vscode event: specifically for launching Workspaces from the page
  vscode:
    - docker:
        # Custom image as development environment
        image: node:20
      services:
        - vscode
        - docker
      stages:
        - name: ls
          script: ls -al
```

## Custom Resource Specifications

You can declare the required development resources through `runner.cpus`, supporting up to `64 cores`, with memory being cpus x 2(GB).

```yaml{4} title=".cnb.yml"
$:
  vscode:
    - runner:
        cpus: 64
      docker:
        build: .ide/Dockerfile
      services:
        - vscode
        - docker
      stages:
        - name: ls
          script: ls -al
```

## Custom Trigger Events

Through `.cnb.yml`, you can declare when to automatically create a development environment based on specific trigger events. Recommended trigger events include:

* [`vscode`](../build/grammar.md#workspaces-events): Create development environment when clicking the `Launch Workspaces` button on repository page
* [`branch.create`](../build/grammar.md#branch-create): Create development environment when creating a branch
* [`api_trigger`](../build/grammar.md#api_trigger): Create development environment through custom API trigger
* [`web_trigger`](../build/trigger-rule.md#web_trigger): Create development environment through custom web page trigger

```yaml{5} title=".cnb.yml"
# Match all branches
(**):
  # Create development environment when creating branch
  branch.create:
    - name: vscode
      services:
        # Declare using vscode service
        - vscode
      docker:
        # Custom development environment
        build: .ide/Dockerfile
      stages:
        - name: Execute custom scripts
          script:
            - npm install
            - npm run start
```

## Custom Availability Timing

By default, Workspaces becomes available after the pipeline preparation (`prepare`) phase completes (when the `code-server` service starts) and before the `stages` tasks execute.

If you want to enter the development environment after executing certain tasks, i.e., delay the timing of entering the development environment, you can use the built-in [vscode:go](../build/internal-steps/README.md#go) task.
When using this task, after starting Workspaces, the `loading` page will delay entering the Workspaces entry selection page until the `vscode:go` task executes.

Note that using the `vscode:go` task will increase waiting time.
Tasks that must be executed before entering the development environment should be placed before `vscode:go`,
while tasks that can be executed after entering the development environment should be placed after `vscode:go`.
**If there are no tasks that must be executed before entering the development environment, there's no need to use `vscode:go`**.

When `stages` tasks fail, whether Workspaces ends depends on:

* Using `vscode:go`: If tasks before `vscode:go` fail, the development environment will be destroyed
* Using `vscode:go`: If tasks after `vscode:go` fail, the development environment will not be destroyed
* Not using `vscode:go`: If `stages` tasks fail, the development environment will not be destroyed

## Custom Pre-destruction Tasks

You can use [`endStages`](../build/grammar.md#endstages) to define tasks that need to be executed before the development environment is destroyed.

```yaml{14-18} title=".cnb.yml"
$:
  vscode:
    - docker:
        image: node:20
      services:
        - vscode
        - docker
      # Tasks to execute after development environment starts
      stages:
        - name: ls
          script: ls -al
      # Tasks to execute before development environment is destroyed
      endStages:
        - name: end stage 1
          script: echo "end stage 1"
        - name: end stage 2
          script: echo "end stage 2"
```