http://nerds.airbnb.com/airflow
blog-post-airflow#configuration-as-code1 "Configuration as code" is a principle we stand by for this purpose. While yaml or json job configuration would allow for any language to be used to generate Airflow pipelines, we felt that some fluidity gets lost in the translation. Being able to introspect code (ipython!, IDEs) subclass, meta-program and use import libraries to help write pipelines adds tremendous value. Note that it is still possible to author jobs in any language or markup, as long as you write Python that interprets these configurations. blog-post-airflow#configuration-as-code1