# Linux

Linux checks resolve logical tools from installed commands, repo-local runtimes,
and user overrides such as `AAS_PYTHON` or `AAS_SAGE`. `precheck` also checks
selected optional Python packages where a skill declares them.
macOS uses the same POSIX launcher path for core installer flows and is covered
by CI for the default lifecycle smoke, but this repository does not yet provide
a separate macOS dependency guide.

Common commands:

```bash
make doctor
make precheck ARGS="--profile research-core"
make plan ARGS="--profile research-core"
make install ARGS="--profile research-core --dry-run"
make lifecycle-test ARGS="--matrix default --platform-shape linux"
make fake-root-lifecycle ARGS="--profile research-core --platform-shape linux"
make verify ARGS="--root <fake-or-real-root>"
```

Useful overrides:

- `AAS_PYTHON`: preferred Python interpreter for `python-runtime` checks
- `AAS_SAGE`: preferred SageMath executable for `sage-runtime` checks
- `PATH`: command discovery for TeX, Git, ripgrep, OCR, Calibre, and other tools

Docker-backed SageMath is also valid on Linux when it is exposed through an
executable wrapper. Put the wrapper on `PATH` as `sage` or point `AAS_SAGE` at
it. The wrapper should support the normal probes used by `precheck`, including
`sage --version` and `sage -c "print(2+2)"`.

The Linux path is also used when inspecting a mounted Windows profile from WSL
or a Linux host. In that case, native Windows executables may be reported as
`present-unverified` because they can be found but not safely executed from the
current substrate.

Related pages: [Dependencies](dependencies.md), [Windows](windows.md),
[Installation](installation.md), [Troubleshooting](troubleshooting.md).