{"id":591,"date":"2025-09-27T21:33:39","date_gmt":"2025-09-27T21:33:39","guid":{"rendered":"https:\/\/camilo.matajira.com\/?p=591"},"modified":"2025-10-01T10:58:21","modified_gmt":"2025-10-01T10:58:21","slug":"ansible-meets-uv","status":"publish","type":"post","link":"https:\/\/camilo.matajira.com\/?p=591","title":{"rendered":"Ansible meets UV"},"content":{"rendered":"\n

Introduction<\/h3>\n\n\n\n

Ansible is still the most powerful Configuration Management tool in 2025. It’s used mainly to configure and manage bare-metal servers and virtual machines.
But can also be used to for network automation, cloud resource provisioning, CICD pipelines, etc.<\/p>\n\n\n\n

Ansible’s popularity (and configuration management tool’s in general) has decreased in recent years, probably due to a shift towards immutable infrastructure (despite that Ansible could be used for this too).
But there are still new applications in which Ansible could shine.<\/p>\n\n\n\n

\n

So why bother with Ansible in 2025? Because it gives you interesting features out of the box:1<\/strong>) Idempotency, 2) Drift detection, 3) a really high level ‘language’. And because used with UV, <\/strong>Ansible can be used as a standalone ‘scripting’ ‘language’, with idempotency and drift detection, <\/strong>again out of the box. For certain tasks, those are killer features.<\/strong> Which tasks? Think for example installation of software; installation of tools; Developer Experience (DevEx) setup; CD part of a CICD pipeline; setup of CI ephemeral runners etc.<\/p>\n<\/div>\n\n\n\n

Why hasn’t it been done before?<\/h3>\n\n\n\n

But historically Ansible, and more specifically ansible-playbooks, haven’t been thought to be used as a standalone script, why?<\/p>\n\n\n\n

    \n
  1. Because installing Ansible in itself is (was) complicated.
    1.1. Because being written in python, Ansible suffers python’s known packaging issues.
    1.2. Because, Ansible versioning has been historically complicated.
    1.3. Because probably, neither the author of the playbook nor the final user are python experts to be able to debug the packaging issues.<\/li>\n\n\n\n
  2. Because Ansible has been used already in a repo with complex inventory structures, complex overrides, with roles that need to be installed. And despite that this is normal, the usual complexity might shy away the usability or applicability of standalone script.<\/li>\n\n\n\n
  3. Because scripting could be done with simpler and more powerful tools like Bash and Make. Make can give us idempotency, but not drift detection out of the box. Bash can’t give neither idempotency nor drift detection, you’ll need to code them yourself.
    The same for python or other scripting language, but they don’t provide a high-level language. At least not high-enough to Bash, Make or Ansible.<\/li>\n\n\n\n
  4. Ansible is too verbose. Probably 3 lines of Bash can do what 50 lines of ansible-playbook does. Yet, if we want idempotency, drift detection and readability we would need to write some extra code.<\/li>\n<\/ol>\n\n\n\n

    (Just to be clear, I’m not advocating replacing Bash or Make with Ansible, that would be insane. What I’m trying to say, is that for certain specific set of tasks, Ansible could be a better fit. What you’ll see later is that I actually use together Make, Bash and Ansible)<\/p>\n\n\n\n

    The UV solution and example<\/h3>\n\n\n\n

    Back to the point, The UV project, has solved one of Ansible’s major issues: the difficulty to install, use and share.<\/strong> You can read about UV here: https:\/\/docs.astral.sh\/uv\/<\/p>\n\n\n\n

    Look at the ansible-playbook below. What is important is the shebang line: it is an executable script. It is a ‘UV run tool’ script (to learn more see https:\/\/docs.astral.sh\/uv\/concepts\/tools\/#relationship-to-uv-run), though in reality it’s an Ansible playbook.
    The only dependency of this script is UV, no need to have python, pip or Ansible installed.
    UV installs python and Ansible for us, in an invisible manner. And now, with some caveats, I can run this script almost anywhere, the script could be distributed. And no one needs to know that it even is an ansible playbook!<\/p>\n\n\n\n

    Below is a script that I carved out from a larger project. Don’t expect to run it as is, its purpose is to exemplify what can be done with Ansible and UV.<\/strong><\/p>\n\n\n\n

    <\/circle><\/circle><\/circle><\/g><\/svg><\/span>