Talk about Pixi in our docs

README.md

@@ -124,7 +124,7 @@ The `--deps` option tells FawltyDeps where to look for your project's declared
 dependencies. A number of file formats are supported:
 
 - `*requirements*.txt` and `*requirements*.in`
-- `pyproject.toml` (following PEP 621 or Poetry conventions)
+- `pyproject.toml` (following PEP 621, Poetry, or Pixi conventions)
 - `setup.py` (only limited support for simple files with a single `setup()`
   call and no computation involved for setting the `install_requires` and
   `extras_require` arguments)

fawltydeps/extract_declared_dependencies.py

@@ -248,7 +248,19 @@ def parse_extra(contents: TomlData, src: Location) -> NamedLocations:
 def parse_pixi_pyproject_dependencies(
     pixi_config: TomlData, source: Location
 ) -> Iterator[DeclaredDependency]:
-    """Extract dependencies from `tool.pixi` fields in a pyproject.toml."""
+    """Extract dependencies from `tool.pixi` fields in a pyproject.toml.
+
+    - [tool.pixi.dependencies] contains mandatory Conda deps
+    - [tool.pixi.pypi-dependencies] contains mandatory PyPI deps
+    - [tool.pixi.feature.<NAME>.dependencies] contains optional Conda deps
+    - [tool.pixi.feature.<NAME>.pypi-dependencies] contains optional PyPI deps
+
+    NOTE: We do not currently differentiate between Conda dependencies and PyPI
+    dependencies, meaning that we assume that a Conda dependency named FOO will
+    map one-to-one to a Python package named FOO. This is certainly not true for
+    Conda dependencies that are not Python packages, and it probably isn't even
+    true for all Conda dependencies that do indeed include Python packages.
+    """
 
     def parse_main(contents: TomlData, src: Location) -> NamedLocations:
         return (

fawltydeps/main.py

@@ -4,10 +4,10 @@
 notebooks (*.ipynb).
 
 Supports finding dependency declarations in *requirements*.txt (and .in) files,
-pyproject.toml (following PEP 621 or Poetry conventions), setup.cfg, as well as
-limited support for setup.py files with a single, simple setup() call and
-minimal computation involved in setting the install_requires and extras_require
-arguments.
+pyproject.toml (following PEP 621, Poetry, or Pixi conventions), setup.cfg, as
+well as limited support for setup.py files with a single, simple setup() call
+and minimal computation involved in setting the install_requires and
+extras_require arguments.
 """
 
 from __future__ import annotations