Problem Definition

There is no option in YAML Specs to clean the working directory after execution of a build.
However, it is possible to do this from the Bamboo UI by choosing "Clean working directory after each build" option under Plan configuration -> Miscellaneous tab.

Suggested Solution

Add a Specs option to clean the working directory after the build (similar to the option we set in the Bamboo UI)

Why this is important

Some builds need clean working directory before each build.

Workaround

One will have to start their definition with script task like below to have a clean working directory:

stages:
  - jobs:
      - scripts:
          - rm -rf ${bamboo.build.working.directory}
          - #your scripts here

However, having this in the script might delete the source code or the artifacts.