Systems

The internal building blocks of ansible-core. These are the cross-cutting subsystems that the apps sit on top of and the plugins hook into. They don't map to a single user-facing CLI; they're the shared machinery.

What's in this section

Page	Subsystem	Code path
Executor	Task scheduler: PlaybookExecutor → TQM → strategies → workers → TaskExecutor	lib/ansible/executor/ + lib/ansible/plugins/strategy/
Plugin loader	Discovers and instantiates plugins across built-in, collections, and user paths	lib/ansible/plugins/loader.py + lib/ansible/utils/collection_loader/
Templating	Hardened Jinja2 with trust tagging — the {{ ... }} engine	lib/ansible/_internal/_templating/ + lib/ansible/template/
Module execution and AnsiBallZ	Wraps a module + its module_utils into a self-contained Python archive shipped to remote hosts	lib/ansible/executor/module_common.py + lib/ansible/_internal/_ansiballz/
Vault encryption	AES-encrypted variables and files at rest	lib/ansible/parsing/vault/
Configuration	Layered config from defaults, ansible.cfg, env, and CLI	lib/ansible/config/ + lib/ansible/utils/path.py

How they relate

graph TD
    CLI["CLI base<br/>lib/ansible/cli/__init__.py"] --> CFG[Configuration]
    CLI --> PL[Plugin loader]
    CLI --> EX[Executor]
    EX --> PL
    EX --> AZ[AnsiBallZ]
    EX --> TPL[Templating]
    AZ --> PL
    TPL --> PL
    CLI --> VLT[Vault]
    PL --> CL[Collection loader]

• Configuration runs first. Almost every other system reads it.
• Plugin loader is initialized early by every CLI; it imports the collection loader.
• Templating is consulted whenever a value is rendered (which is constantly).
• Executor drives the playbook lifecycle; it talks to the plugin loader to find action/connection/strategy plugins.
• AnsiBallZ is invoked from action plugins inside the executor's worker children.
• Vault is loaded by the dataloader, also early.

Cross-links

• Apps for what sits on top.
• Plugins for the user-extensible interfaces these systems expose.
• Primitives for the playbook objects the executor walks.