ext-calendarius

Public contract surface for the calendarius extension, per the ext-<id> convention and the extension backend architecture standard. Depends only on the standard library — never on another extension or the calendarius implementation.

Created 2026-07-09 to close the compliance gap recorded in the ecosystem review (backstage/spec/research/ecosystem-review-2026-07/): calendarius was the only widely-consumed extension without a definition repo, so consumers (e.g. the eventius adapter in sneat-go) imported calendarius/backend implementation types directly.

Contents

• backend/ — Go module github.com/sneat-co/ext-calendarius/backend
  • calendariusmodels — shared vocabulary: HappeningSpec, HappeningBrief
  • facade4calendarius — HappeningsFacade, the interface consumers depend on; the host (sneat-go) implements it once over the calendarius implementation facade and injects it into consuming extensions
• frontend/ — Nx workspace whose ext-calendarius-contract project publishes @sneat/extension-calendarius-contract. This repository is its sole source.

Migration plan (grow-as-touched, no big bang)

1. ✅ Seed vocabulary + facade interface (this repo, backend/v0.x).
2. sneat-go/pkg/modules/eventius adapter: implement facade4calendarius.HappeningsFacade and keep the eventius port satisfied by it; new calendar consumers (bookius, school-portal) depend on this interface instead of writing new ports.
3. Extract further shared DTOs from calendarius/backend/dto4calendarius here as second consumers appear (dbo4calendarius storage types stay private — see the standard's moves-vs-stays rule).
4. ✅ Move @sneat/extension-calendarius-contract from sneat-libs into this repository. The implementation packages live in calendarius/frontend.