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The reference implementation of the Common Workflow Language standards


What cwltool can do for you

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This is the reference implementation of the Common Workflow Language open standards. It is intended to be feature complete and provide comprehensive validation of CWL files as well as provide other tools related to working with CWL.

cwltool is written and tested for Python 3.x {x = 6, 7, 8, 9, 10, 11}

The reference implementation consists of two packages. The cwltool package is the primary Python module containing the reference implementation in the cwltool module and console executable by the same name.

The cwlref-runner package is optional and provides an additional entry point under the alias cwl-runner, which is the implementation-agnostic name for the default CWL interpreter installed on a host.

cwltool is provided by the CWL project, a member project of Software Freedom Conservancy and our many contributors.

Programming languages
  • Python 80%
  • Common Workflow Language 18%
  • Makefile 1%
  • Shell 1%
</>Source code

Participating organisations

Common Workflow Language


Related projects

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