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Limitations

ds does not strive to be an all-in-one tool for every project and is not a replacement for package management tools or make. Here are some things that are not supported or not yet implemented.

  • Lifecycle Events (experimental support via --pre/--post)
  • call Tasks (supported for Python only)
  • Partial Support: Makefile format (see #68)
  • In Progress: Remove Python Dependency (see #46)

Lifecycle Events

Some task runners (all the node ones, pdm, composer) support running additional pre- and post- tasks when you run a task. However, this obscures the relationship between tasks and can create surprises if you happen to have two tasks with unfortunate names (e.g., pend and prepend). By default, ds does not automatically run pre/post tasks (see #24).

Experimental Feature

You can enable lifecycle events using the --pre and/or --post flags:

ds --pre --post build
# Looks for: prebuild, pre_build, or pre-build (runs first)
# Then runs: build
# Then looks for: postbuild, post_build, or post-build (runs last)

See Pre/Post Hooks for more details.

A more explicit alternative is to use composite commands to clearly describe the relationship between a task and its pre- and post- tasks.

# Implicit: hidden assumption that `build` calls `prebuild` first.
[scripts]
prebuild = "echo 'prebuild'"
build = "echo 'build'"

# Explicit: clear relationship between tasks.
[scripts]
prebuild = "echo 'prebuild'"
build = ["prebuild", "echo 'build'"]

call Tasks

Some task runners support special call tasks which get converted into language-specific calls. For example, both pdm and rye can call into python packages and composer can call into a PHP module call.

Python call tasks are supported in pyproject.toml (for pdm, rye, poetry, and ds-style configurations):

[tool.ds.scripts]
# Call a module (becomes: python -m http.server)
serve = { call = "http.server" }

# Call a function (becomes: python -c "import sys; import myapp as _1; sys.exit(_1.main())")
run = { call = "myapp:main" }

# Call with arguments
greet = { call = "myapp:greet('Hello')" }

Python Only

call tasks are only supported in pyproject.toml. PHP call tasks from composer.json are not supported (see #32).

If you prefer explicitness, you can write out the call directly:

# {"call": "pkg"} becomes:
python -m pkg

# {"call": "pkg:main('test')"} becomes:
python -c "import sys; import pkg as _1; sys.exit(_1.main('test'))"