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@@ -80,3 +80,31 @@ command -v -o file.txt
 ```
 
 Long options are self-documenting and make scripts and examples easier to understand without consulting help text. Short options are acceptable for interactive use but should not appear in committed code, documentation, or examples.
+
+## Green-Field Project Setup
+
+When setting up a new project, code-quality and developer-experience tooling must be included from the start and integrated into the development workflow. The principles below use Python as a concrete example, but apply generally to any language ecosystem.
+
+### Python Tooling
+
+Use **uv** to manage dependencies and create the project virtual environment. All work must be performed inside the venv. Additionally, install and configure the **pre-commit** hook manager with a baseline DevEx toolset:
+
+- **ruff** — linting and formatting
+- **mypy** — static type checking
+- **tach** — structural/dependency boundary checks
+
+Configure all tools for their strictest check levels by default. Include a `py.typed` marker file in every package to signal PEP 561 compliance.
+
+### Line Length
+
+Do not manually break lines to conform to a line-length limit. Automated code formatters (ruff, gofmt, etc.) handle this for source code. Write unbroken lines in text and Markdown files (e.g., README.md) as well. This also applies to one-off files outside of a project context.
+
+### Licensing (REUSE)
+
+In all projects, install a **pre-commit hook for the REUSE tool** to lint licensing information and ensure every file has correct SPDX headers.
+
+Default license assignments:
+
+- **GPL-3.0-or-later** — source code files in coding projects
+- **CC-BY-SA-4.0** — documentation files (README, user guides, etc.); also the default project license for non-coding projects
+- **CC0-1.0** — project configuration files (e.g., `pyproject.toml`, `tach.toml`) and small utility scripts or Makefiles that are not core to the implemented logic