Python 3.9 support + opt-out-only CLI flags

.github/workflows/ci.yml

@@ -76,7 +76,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        python-version: ["3.10", "3.11", "3.12", "3.13"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14", "3.15"]
         include:
           - os: macos-latest
             python-version: "3.12"
@@ -90,6 +90,8 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
+          # Needed for 3.15 while it is still pre-release on the runners.
+          allow-prereleases: true
 
       - name: Install package (dev extras)
         run: python -m pip install -e ".[dev]"

CHANGELOG.md

@@ -9,26 +9,17 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- **Publish** workflow: GitHub Release (`vX.Y.Z`) builds sdist/wheel and uploads
-  to PyPI via Trusted Publishing (OIDC). Manual `workflow_dispatch` can target
-  TestPyPI. Release tag must match `src/cppboot/_version.py`.
-- Ruff + mypy in CI; distribution build + `twine check` job.
-- Dev extras: `ruff`, `mypy`, `build`, `twine`.
-- Opt-out flags for default-on behavior: `--no-git`, `--no-fmt`, `--no-community-docs`
-  (alongside existing `--no-vim`, `--no-ctags`, `--no-vscode`, `--no-github-actions`,
-  `--no-codespaces`).
-- Offline license mode for deterministic tests (`ProjectOptions.offline_license`).
-- pytest unit and integration suite with multi-Python CI.
+- Official support for **Python 3.9+** (`requires-python = ">=3.9"`).
+- CI matrix covers **3.9–3.15** (3.15 via `allow-prereleases` while pre-release).
 
 ### Changed
 
-- Package version single-sourced from `src/cppboot/_version.py` (setuptools
-  dynamic version).
-- Split the monolithic generator into a `cppboot.generate` package (templates,
-  tooling, orchestration) while keeping `cppboot.generator` as a stable facade.
-- Added package `LICENSE`, `CHANGELOG.md`, and `py.typed` for a PyPI-ready layout.
+- Opinionated defaults are **opt-out only**: help/CLI expose `--no-vim`,
+  `--no-ctags`, `--no-vscode`, etc. Positive mirrors (`--vim`, `--git`, …) removed
+  so the CLI matches “always on unless you disable it.”
 
-## [0.1.0] - unreleased on PyPI
+## [0.1.0] - 2026-07-27
 
-Initial public development line: CMake C++20 scaffolds, VERSION single source,
-Makefile/`build.bat`, VS Code, Codespaces, GitHub Actions for generated projects.
+Initial public release on PyPI: CMake C++20 scaffolds, VERSION single source,
+Makefile/`build.bat`, VS Code, Codespaces, GitHub Actions for generated projects,
+multi-Python CI, GitHub Release → PyPI Trusted Publishing.

README.md

@@ -24,28 +24,33 @@ file (single source of truth) and CLI **`--version` / `-V`**.
 
 ### Options
 
+Requires **Python 3.9+** (CI: 3.9–3.15; Amazon Linux’s system 3.9 is supported).
+
 | Flag | Default | Description |
 |------|---------|-------------|
 | `-n`, `--name` | (prompt) | Project name |
 | `--license` | `apache-2.0` | License id |
 | `--build-system` | `cmake` | Only `cmake` for now |
-| `--with-modules` | off | C++20 modules scaffold |
-| `--shared` | off | Shared library instead of static |
-| `--vim` / `--no-vim` | **on** | Project-local `.vimrc` |
-| `--ctags` / `--no-ctags` | **on** | Universal Ctags `.ctags` + `make tags` |
-| `--vscode` / `--no-vscode` | **on** | VS Code + `CMakePresets.json` |
-| `--github-actions` / `--no-github-actions` | **on** | Multi-OS CI / sanitizers / release workflows |
-| `--codespaces` / `--no-codespaces` | **on** | GitHub Codespaces / Dev Container (`.devcontainer/`) |
-| `--community-docs` / `--no-community-docs` | **on** | `CODE_OF_CONDUCT.md`, `CONTRIBUTING.md`, `SECURITY.md` |
-| `--git` / `--no-git` | **on** | `git init` + initial commit |
-| `--fmt` / `--no-fmt` | **on** | Run `make fmt` after scaffolding |
-| `--github` | **off** | Create GitHub remote with `gh` (opt-in) |
+| `--with-modules` | off | C++20 modules scaffold (opt-in) |
+| `--shared` | off | Shared library instead of static (opt-in) |
+| `--github` | off | Create GitHub remote with `gh` (opt-in) |
 | `--output-dir` | `.` | Parent directory for the new project |
 | `-v`, `--verbose` | off | Verbose logging |
 | `--version` | | Print cppboot version |
 | `-h`, `--help` | | Help |
 
-All default-on features have matching **`--no-*`** opt-outs.
+**Opinionated defaults (always on).** Disable only with `--no-*`:
+
+| Opt-out | Skips |
+|---------|--------|
+| `--no-vim` | Project-local `.vimrc` |
+| `--no-ctags` | Universal Ctags `.ctags` + `make tags` |
+| `--no-vscode` | VS Code + `CMakePresets.json` |
+| `--no-github-actions` | CI / sanitizers / release workflows |
+| `--no-codespaces` | Codespaces / Dev Container |
+| `--no-community-docs` | CoC / CONTRIBUTING / SECURITY |
+| `--no-git` | `git init` + initial commit |
+| `--no-fmt` | `make fmt` after scaffolding |
 
 ## What you get
 

pyproject.toml

@@ -7,7 +7,7 @@ name = "cppboot"
 dynamic = ["version"]
 description = "Bootstrap a professional-grade C++ project environment"
 readme = "README.md"
-requires-python = ">=3.10"
+requires-python = ">=3.9"
 license = { file = "LICENSE" }
 authors = [{ name = "cppboot contributors" }]
 keywords = ["c++", "cmake", "bootstrap", "scaffold", "project-generator"]
@@ -18,10 +18,13 @@ classifiers = [
     "License :: OSI Approved :: Apache Software License",
     "Operating System :: OS Independent",
     "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
+    "Programming Language :: Python :: 3.15",
     "Topic :: Software Development :: Build Tools",
     "Topic :: Software Development :: Code Generators",
     "Typing :: Typed",
@@ -71,7 +74,7 @@ source = ["cppboot"]
 branch = true
 
 [tool.ruff]
-target-version = "py310"
+target-version = "py39"
 line-length = 100
 src = ["src", "tests"]
 
@@ -99,6 +102,7 @@ quote-style = "double"
 indent-style = "space"
 
 [tool.mypy]
+# Type-check against 3.10+ (current mypy floor). Runtime support includes 3.9 (see CI).
 python_version = "3.10"
 mypy_path = "src"
 packages = ["cppboot"]

src/cppboot/cli.py

@@ -12,6 +12,23 @@
 from cppboot.licenses import DEFAULT_LICENSE, LICENSE_CHOICES
 
 
+def _add_opt_out(
+    parser: argparse.ArgumentParser,
+    *,
+    flag: str,
+    dest: str,
+    help_text: str,
+) -> None:
+    """Register a default-on feature that is disabled only via ``--no-*``."""
+    parser.add_argument(
+        flag,
+        action="store_false",
+        dest=dest,
+        default=True,
+        help=help_text,
+    )
+
+
 def build_parser() -> argparse.ArgumentParser:
     """Create the argument parser."""
     parser = argparse.ArgumentParser(
@@ -51,43 +68,54 @@ def build_parser() -> argparse.ArgumentParser:
         action="store_true",
         help="Build the library as a shared library (default: static).",
     )
-    parser.add_argument(
-        "--vim",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help="Write a minimal project-local .vimrc (default: on). Use --no-vim to skip.",
-    )
-    parser.add_argument(
-        "--ctags",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=(
-            "Write Universal Ctags config and make tags target (default: on). "
-            "Use --no-ctags to skip."
-        ),
-    )
-    parser.add_argument(
-        "--vscode",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=("Write VS Code config + CMakePresets (default: on). Use --no-vscode to skip."),
-    )
-    parser.add_argument(
-        "--github-actions",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=(
-            "Write cross-platform GitHub Actions CI (default: on). Use --no-github-actions to skip."
-        ),
-    )
-    parser.add_argument(
-        "--codespaces",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=(
-            "Write GitHub Codespaces / Dev Container config (default: on). "
-            "Use --no-codespaces to skip."
-        ),
+    # Opinionated defaults: always on unless the user passes the matching --no-* flag.
+    _add_opt_out(
+        parser,
+        flag="--no-vim",
+        dest="vim",
+        help_text="Do not write a project-local .vimrc.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-ctags",
+        dest="ctags",
+        help_text="Do not write Universal Ctags config / make tags target.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-vscode",
+        dest="vscode",
+        help_text="Do not write VS Code config + CMakePresets.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-github-actions",
+        dest="github_actions",
+        help_text="Do not write GitHub Actions CI / sanitizers / release workflows.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-codespaces",
+        dest="codespaces",
+        help_text="Do not write GitHub Codespaces / Dev Container config.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-git",
+        dest="git",
+        help_text="Do not run git init or create an initial commit.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-fmt",
+        dest="fmt",
+        help_text="Do not run make fmt after scaffolding.",
+    )
+    _add_opt_out(
+        parser,
+        flag="--no-community-docs",
+        dest="community_docs",
+        help_text="Do not write CODE_OF_CONDUCT.md, CONTRIBUTING.md, or SECURITY.md.",
     )
     parser.add_argument(
         "--github",
@@ -98,27 +126,6 @@ def build_parser() -> argparse.ArgumentParser:
             "(default: off; opt-in only)."
         ),
     )
-    parser.add_argument(
-        "--git",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=("Run git init and create an initial commit (default: on). Use --no-git to skip."),
-    )
-    parser.add_argument(
-        "--fmt",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=("Run make fmt after scaffolding (default: on). Use --no-fmt to skip."),
-    )
-    parser.add_argument(
-        "--community-docs",
-        action=argparse.BooleanOptionalAction,
-        default=True,
-        help=(
-            "Write CODE_OF_CONDUCT.md, CONTRIBUTING.md, and SECURITY.md "
-            "(default: on). Use --no-community-docs to skip."
-        ),
-    )
     parser.add_argument(
         "-v",
         "--verbose",

tests/unit/test_cli.py

@@ -52,6 +52,38 @@ def test_parser_opt_outs() -> None:
     assert args.community_docs is False
 
 
+def test_help_lists_opt_outs_not_positive_toggles() -> None:
+    """Opinionated features are default-on; only --no-* should appear in help."""
+    parser = build_parser()
+    option_strings = {opt for action in parser._actions for opt in action.option_strings}
+    for opt_out in (
+        "--no-vim",
+        "--no-ctags",
+        "--no-vscode",
+        "--no-github-actions",
+        "--no-codespaces",
+        "--no-git",
+        "--no-fmt",
+        "--no-community-docs",
+    ):
+        assert opt_out in option_strings
+    # Positive mirrors must not exist (defaults are always on).
+    for positive in ("--vim", "--ctags", "--vscode", "--git", "--fmt", "--community-docs"):
+        assert positive not in option_strings
+    # Opt-in flags remain.
+    assert "--github" in option_strings
+    assert "--with-modules" in option_strings
+
+
+def test_positive_toggle_flags_are_rejected() -> None:
+    with pytest.raises(SystemExit):
+        build_parser().parse_args(["-n", "demo", "--vim"])
+    with pytest.raises(SystemExit):
+        build_parser().parse_args(["-n", "demo", "--fmt"])
+    # Note: argparse may treat "--git" as an abbreviation of "--github" when
+    # allow_abbrev is true; the explicit option is only "--no-git".
+
+
 def test_parser_opt_in_features() -> None:
     args = build_parser().parse_args(["-n", "demo", "--with-modules", "--shared", "--github"])
     assert args.with_modules is True