This document discusses Apache Airflow and Google Cloud Composer. It begins by providing background on Apache Airflow, including that it is an open source workflow engine contributed by Airbnb. It then discusses how Codementor uses Airflow for ETL pipelines and machine learning workflows. The document mainly focuses on comparing self-hosting Airflow versus using Google Cloud Composer. Cloud Composer reduces efforts around hosting, permissions management, and monitoring. However, it has some limitations like occasional zombie tasks and higher costs. Overall, Cloud Composer allows teams to focus more on data logic and performance versus infrastructure maintenance.