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Quick Demo

A 5-minute, self-contained walkthrough that builds and runs a tiny "thermostat"-style C program end-to-end via ebuild build.

Prerequisites

  • Python 3.8+
  • A system C compiler (gcc or clang)
  • The ninja pip package — a system ninja binary alone is not enough, since ebuild invokes python -m ninja internally.

1. Set up a virtual environment

python3 -m venv .venv
source .venv/bin/activate

2. Install ebuild

pip install -e '.[dev]'   # falls back to: pip install -e .

If this fails with an error like:

ERROR: File "setup.py" or "setup.cfg" not found. Directory cannot be installed
in editable mode: ...
(A "pyproject.toml" file was found, but editable mode currently requires a
setuptools-based build.)

your virtualenv's pip is too old to support pyproject.toml-only editable installs (PEP 660). Upgrade it first, then retry:

python3 -m pip install --upgrade pip
pip install -e '.[dev]'

3. Run the test suite (optional, but confirms your install is healthy)

pytest

You should see all tests pass.

4. Build and run the example

cd examples/hello_world
cat build.yaml   # see how the project is described
ebuild build

Expected output ends with:

[info] Auto-detected backend: ninja
   Resolving dependency graph...
   Resolving toolchain...
   Generating build.ninja in _build/...
[ok] Generated _build/build.ninja
[ok] Generated _build/compile_commands.json
   Invoking ninja...
[ok] Build completed successfully.

Run the built binary:

./_build/hello
Hello from EoS Build System!

Troubleshooting

No-root / PEP 668 environments

Using a virtualenv (step 1) avoids Python's PEP 668 "externally managed environment" errors entirely, since you're not installing into the system Python. If you still hit editable-install errors inside the venv, see the pip-upgrade note in step 2 above — that resolves the case actually encountered while writing this guide.

Building without a system compiler

Not yet verified. This guide's build step was tested with a system gcc available. Behavior when no system compiler is present (e.g. cross-compile-only environments) has not been confirmed and needs a maintainer with the appropriate toolchain setup to document. If you hit this, please open an issue with the exact error output.