wowi42

English is not my first language, so I lean on an LLM to clean up the frenchisms, but the ideas are mine :-)

Hey, fair pushback, let me try to clear up a couple of points because I think there are some genuine misconceptions worth untangling.

On footguns. Totally hear you that "Python lets you do anything" feels like a footgun. The flip side that I think gets missed: because it is real Python, you can actually test it. Pytest, mypy, ruff, jump-to-definition, refactor-rename, all of it just works. Unit-testing a 400-line YAML role with nested Jinja conditionals is genuinely hard, and that gap is what pushed me toward PyInfra in the first place.

On "importing Python libraries introduces bugs". This one I think is worth a closer look, because the mechanics are not what they appear. PyInfra does not run Python on your servers. It runs Python on your control node to plan the change, then transpiles each operation to plain POSIX shell and pipes that over SSH. If you run with `-vvv` you can see it: `sh -c '...'` and nothing else on the wire. The target needs zero Python, zero agent, zero runtime. So whatever library you imported into your deploy script ran locally, produced a string of shell, and that string is what touches the box. A bug in some PyPI dependency cannot throw mid-operation on the host, because there is no Python on the host to throw it. Worth noting that Ansible, by contrast, ships a Python interpreter and module code to the target for most tasks, so if anything the library exposure on the executing side is larger there, not smaller.

On the control node, sure, you have dependencies, same as Ansible has Jinja2, PyYAML, paramiko, cryptography, and a long tail of Galaxy collections of varying quality. PyInfra has a stable API, solid test coverage, idempotent operations, and a real two-phase model (gather facts, then apply) so the apply phase is deterministic generated shell rather than arbitrary code running on the box.

On YAML keeping you on the paved path. I really wanted this to be true for years, honestly. In practice, the moment you need a conditional you end up writing `{% if %}` inside a quoted string inside a map inside a list inside a role, with no type system, no debugger, and a few sharp edges in the parser (`no` as boolean, leading zeros as octal in YAML 1.1, tab/space mixing failing without a useful pointer). And the escape hatch when Jinja-in-YAML cannot express what you need is... writing a custom Python module. So you end up writing Python anyway, just with worse tooling around it.

The way I would put it: PyInfra is Python where Python helps (writing, testing, planning) and shell where shell belongs (executing on the host). Happy to dig into any specific footgun you have run into though, those are usually the most useful conversations.

Ah shit...

Glad it clicked. The Ansible vs PyInfra docs gap isn't really preference, YAML plus Jinja plus a custom DSL is just more cognitive load than plain Python with type hints. Once you can grep the source and read it like normal code, going back feels rough. On the restart bug: if it resurfaces, an issue on GitHub with the OS, connector (ssh/local/docker), and raw output would help a lot. The 3.x line cleaned up a bunch around connection handling and output buffering, so there's a decent chance it's already fixed. Thanks for the video, will watch. Hands-on intro content is exactly what the project needs more of.

we could put it on our roadmap of examples :-)

Disclosure: PyInfra core contributor here.

We just shipped 3.8.0.

PyInfra is an agentless infrastructure automation tool. Same job description as Ansible, Salt, Chef. SSH into hosts, describe desired state, it diffs and converges. No agent, no central server, no daemon.

The difference: your "playbook" is just Python. Not Python cosplaying as YAML. Not Jinja smuggled inside YAML inside a Helm chart inside a Kustomize overlay. Actual Python:

    from pyinfra.operations import apt, files, server

    apt.packages(packages=["nginx"], update=True)
    files.template(src="nginx.conf.j2", dest="/etc/nginx/nginx.conf")
    server.service(service="nginx", running=True, enabled=True)

Idempotent operations. Facts gathered from hosts, branched on with normal `if` statements. Real loops, real imports, a real debugger, real type hints. Your editor autocompletes arguments because, brace yourself, they are just function signatures.

About YAML. Wonderful format. For about eleven minutes. Then someone needs an `if`, and you have `{% if %}` inside a string inside a list inside a map. Then someone types `no` as a country code for Norway and it ships to prod as `False`. Then someone indents with a tab and the parser dies without saying where. Congratulations, you reinvented a programming language. Badly. The honest move is to admit you wanted code, then write code.

PyInfra skips the eleven good minutes and goes straight to code.

Release notes in the link. Happy to answer questions.

Infrastructure as Code, not infrastructure as YAML.

Author here.

It will be more clear once the video is released :-)

When are you planning to release it?