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cyberuni/sdd2

v0.1.0MIT

Spec-Driven Development, second generation — the SDD process plugin and its CLI.

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cyber-sdd-2

The next generation of Spec-Driven Development, built iteratively alongside the shipped cyber-sdd plugin so the two can coexist in one repository and one marketplace.

It has two sides, following the cyber-asana shape:

  • Plugin side — plugin.json plus skills/, loaded by Claude Code, Cursor, Codex, and Copilot CLI through the repository's local marketplace.
  • CLI side — cyber-sdd-2, the deterministic engine the skills call into instead of re-deriving work in prose.

Status

Scaffold. The CLI exposes --version and --help; the plugin registers the sdd2 gateway skill. It also ships the spec skill, which writes and reviews the design spec. Everything else is still to be built.

Next: the functional spec

The spec skill covers the design spec: what a consumer of a capability is judged against. The functional spec beneath it is missing: the spec colocated with the implementation, holding internal contracts, module behavior, and scenarios. Until it exists, SDD 2 has no counterpart to the first generation's .feature suite, so work on a first-generation project spec stays with the sdd plugin's start-mission.

To settle, in a session of its own:

  • What the functional spec holds, and how it binds to the design spec's criterion IDs.
  • Its test form: native, deterministic tests of the project's stack, with no .feature file for an agent to run (decision D11 in .research/design-spec-criteria).
  • Who produces it and who judges it.
  • How the spec skill's criteria (C1 to C9) relate to the draft criteria governance, which numbers its own criteria from C1 as well.
  • When start-mission hands spec work to SDD 2.

Development

pnpm --filter cyber-sdd-2 build
pnpm --filter cyber-sdd-2 test
pnpm --filter cyber-sdd-2 typecheck