Changelog for 0.10.4 Ansible 2.2.1.0 shipped with a hard dependency on Jinja2 < 2.9 [1]. Since Flask has a requirement on Jinja2 >= 2.4, it would pick up 2.9.4 first and then disregard Ansible's requirement. [1]: https://github.com/ansible/ansible/commit/6c6570583f6e74521e3a4f95fe42ffddb69634fe