Presets

Archetype presets name project shapes; library is the default

Id: a14ee38b-12ed-49c8-b452-12b330cf9d10 Type: decision Status: active Evidence: confirmed Source: ADR-016 (docs/adr/016-archetype-based-presets.md); the preset mechanism it reshapes came from PR #141; ADR-025 and ADR-039 for the two toggles every preset seeds Revisit when: a distinct service/worker archetype (worker + broker + database) proves common enough to be a fifth choice See: standalone-executables.md#three-architecture-named-executable-toggles-instead-of-one-brand-toggle — d5aed1a0-0b7c-4ac3-9d75-fb9568d9e34d — as of 2026-10-11

The preset question offers library (default; seeds examples), tool (cli, tui, pydantic_settings), web (web with FastAPI, pydantic_settings, postgres, redis) and full (everything). Every preset also seeds docs and pypi_publish on (ADR-025, ADR-039). A preset only seeds toggle defaults through the hidden preset_map; every toggle is still asked and stored. tool seeds none of the standalone-executable toggles, and web seeds neither worker, MCP nor the database UIs.

Reason: the earlier minimal/standard/full/custom ladder answered "how much tooling" while adopters think in shapes — a library, a PyPI-shipped CLI/TUI tool, a web app. standard was CLI-lite under a size name, nothing named the library shape, and custom existed only to keep --defaults output byte-identical when presets were introduced — meaningless once every preset is tunable. library is the default because an unattended run should produce the smallest, most conservative surface. tool is PyPI-first because the maintainer ships tools mostly via PyPI and freezes them only occasionally; one deliberate flip beats a default most tools would turn back off.

Rejected alternative: keep custom as a migration cushion — presets had shipped only days earlier, so the cushion protected almost nobody.

Consequence: bare --defaults output changed from the custom set to the library set, intentionally. Stored include_* answers drive rendering, so copier update on existing projects is unaffected apart from a one-time re-prompt of the preset question when its stored value is no longer a valid choice. The template-ci minimal scenario adds include_examples=false to stay a true core-only render.

The example input file holds identity answers and a preset only

Id: ef5a9b93-2be9-4b18-a354-4a6c174207fe Type: decision Status: active Evidence: confirmed Source: ADR-016 (docs/adr/016-archetype-based-presets.md) Revisit when: the identity questions gain defaults, or non-interactive generation gets another data source

.example-input.yml carries only the no-default identity answers, the free-form keywords and preset: library; the per-toggle include_*: false lines were removed. The file is kept, not deleted.

Reason: removing the toggle list deletes the recurring maintenance step "update the example input when a toggle is added", so the file becomes stable. It stays because the identity fields have no defaults and giving them defaults would be a footgun — a bare --defaults run would emit a project literally named example owned by octocat — while non-interactive generation (the example task, the CI render job) still needs a data source. The render harness is unaffected; it supplies its own identity dictionary through Copier's API.

Rejected alternative: remove the file and give the identity questions defaults — the footgun above.