Bitbucket "We couldn't parse your bitbucket-pipelines.yml"

By Kaveh Alemi·Latchkey

This is a raw YAML syntax failure, not a schema problem. The parser could not turn the file text into a document at all - usually bad indentation, a tab, or an unbalanced quote.

What this error means

Bitbucket rejects the file with "We couldn't parse your bitbucket-pipelines.yml" and a line/column reference. Unlike a configuration error, the structure was never even understood - the YAML itself is malformed.

We couldn't parse your bitbucket-pipelines.yml file.
mapping values are not allowed here
  in "bitbucket-pipelines.yml", line 6, column 14

Common causes

Bad indentation or a tab character

YAML requires consistent space-based indentation. A tab, or a line indented to the wrong level, breaks the parser before it can interpret keys.

Unquoted special characters or unclosed quotes

A value containing :, {, or #, or a string with a missing closing quote, makes the parser misread where a mapping or scalar ends.

How to fix it

Fix indentation and quoting at the reported line

Open the file at the line/column Bitbucket names. Replace tabs with spaces and quote values that contain special characters.

# wrong: tab indent + unquoted colon
pipelines:
	default:
    - step:
        script:
          - echo time: now
# right
pipelines:
  default:
    - step:
        script:
          - echo "time: now"

Lint the YAML locally before pushing

yamllint bitbucket-pipelines.yml
# or a quick parse check
python -c "import yaml,sys; yaml.safe_load(open('bitbucket-pipelines.yml'))"

How to prevent it

• Configure your editor to insert spaces, never tabs, in YAML.
• Run a YAML linter in a pre-commit hook.
• Quote any string containing :, #, {, or }.

Frequently asked questions

Related guides

References

• GitHub Actions documentation