FeatherSpec 1.2.0 — Versioned & Updatable

Added

• Versioning: the template carries a FeatherSpecVersion: stamp in AGENTS.md's managed
  settings block; releases are annotated git tags surfaced as GitHub Releases, recorded here
  and in the version ledger.
• /sdd-featherspec-update: check the installed template version (check mode works even
  on customized, unstamped projects via feature probes) and update safely — fetches the
  recorded base and the target release as real trees, classifies every file by canonical-hash
  three-way comparison, previews everything before writing, migrates around preserved
  customizations, surfaces conflicts instead of choosing sides, keeps a rollback point,
  validates the result mechanically, and moves the version stamp only after success.
  Resumable at any point; re-running after success is a free health check.
• Version ledger: an append-only appendix in the update command's body recording
  per-release semantic migration knowledge back to 0.1.0 — renames, key migrations, slot
  edits, data notes, semantic flips, and version probes for unstamped projects.

Changed

• AGENTS.md: the managed settings block gains the version stamp and is now managed by
  /sdd-setup and /sdd-featherspec-update; the DocLanguage comment is condensed to one
  line to keep the constitution under its line target; .sdd-update/ joins the volatile,
  gitignored working locations.

FeatherSpec 1.1.0 — Brownfield Deep Scan

Added

• /sdd-architecture-scan: deep, resumable, budget-cascaded analysis of an existing
  codebase producing an architecture fingerprint — brownfield onboarding for both Claude
  Code and GitHub Copilot.
• sdd-scout explorer subagent for both tools (.claude/agents/sdd-scout.md,
  .github/agents/sdd-scout.agent.md).
• Path-scoped rule for curated module maps (.claude/rules/architecture-map.md).
• Scan-only locations: .architecture/ (curated module maps) and .sdd-scan/ (volatile
  working state, gitignored).
• /sdd-setup asks new-vs-existing project and routes existing software into the deep scan.
• The architecture snapshot header tracks the last deep scan alongside the last
  reconciliation.

Changed

• /sdd-architecture-update recommends /sdd-architecture-scan instead of guessing when
  drift is too large or the area is unmapped.
• Constitution eviction rules: gates, ask-first boundaries and non-negotiables may never be
  evicted from always-loaded context.
• README: brownfield onboarding path documented up to enterprise scale.

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Retroactive release — tagged 2026-08-26 to version the pre-release history. Original date: 2026-08-26.

FeatherSpec 1.0.0 — Stabilization

Added

• Always-loaded Progress & state sync gate: plan checkbox, traceability row and
  activeContext.md must move in the same change set as the code; "done" requires plan,
  active context and code to agree.
• projectbrief.md wired into the working loop: /sdd-specify and /sdd-compile read and
  reconcile against it.

Changed

• Architecture updates now run unprompted: agents execute /sdd-architecture-update
  themselves in the same change set on structural drift (previously: propose and wait).
• All commands hardened against audit findings: tightened gates in /sdd-clarify,
  /sdd-compile, /sdd-lifecycle, /sdd-plan, /sdd-specify, /sdd-setup,
  /sdd-style-update.
• Preference capture triggers in any language and on "remember this"-style requests.

Removed

• docs/history/ (the template's own build specs): the template ships fully blank.

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Retroactive release — tagged 2026-08-26 to version the pre-release history. Original date: 2026-08-04.

FeatherSpec 0.4.0 — Clarify & the Verification Chain

Added

• /sdd-clarify: adversarial pass over a finished spec — contradictions, ambiguity,
  untestable criteria, implementation posing as intent, missing failure modes — ending in
  one question.
• Closed verification chain: criterion → step → code → test → Verified: → verdict. Plan
  steps carry a Verified: field; traceability gains a Test column and the state vocabulary
  open | built | verified.
• Five acceptance-criterion shapes (always-true, event, state, unwanted behaviour, optional
  feature) with shall/should discipline and a falsifiability test.
• Non-negotiables gain an Ask first tier and a documented fast path for changes
  smaller than their spec.
• Project logo.

Changed

• /sdd-compile re-derives readiness from the repository, not from ticked checkboxes, and
  returns NOT READY when the suite did not run.
• /sdd-lifecycle requires recorded evidence before a spec moves to done/.
• Copilot persona reduced to a thin loader; drifted rule copies removed.
• README rewritten for fast onboarding; detail moved to the wiki.
• The template's own build specs moved out of .specs/done/ so a fresh clone starts with an
  empty spec numbering.

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Retroactive release — tagged 2026-08-26 to version the pre-release history. Original date: 2026-08-03.

FeatherSpec 0.3.0 — Commands & Persisted Plans

Added

• Persisted plans: /sdd-plan writes NNNN-slug.plan.md beside its spec — baby steps with
  per-step Verify lines, a current-step pointer, a handoff block and a
  criteria→steps→code traceability table; three modes (plan, resume, re-plan).
• Plan upkeep rule (.claude/rules/plans.md); /sdd-lifecycle moves spec and plan as a
  pair.
• .github/prompts/*.prompt.md thin loaders giving GitHub Copilot slash commands.

Changed

• Breaking (pre-1.0): command bodies moved from .claude/skills/*/SKILL.md to
  .claude/commands/*.md; skills removed entirely so no command description is ever
  advertised to the model. .vscode/settings.json swaps chat.agentSkillsLocations for
  chat.promptFilesLocations.

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Retroactive release — tagged 2026-08-26 to version the pre-release history. Original date: 2026-08-03.

FeatherSpec 0.2.0 — Product-Owner Interview

Changed

• /sdd-specify became an adaptive product-owner interview producing a lean spec with
  testable acceptance criteria.

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Retroactive release — tagged 2026-08-26 to version the pre-release history. Original date: 2026-08-03.

FeatherSpec 0.1.0 — Bootstrap

Added

• Initial shared-source hybrid SDD template: one constitution (AGENTS.md) loaded by Claude
  Code and GitHub Copilot through thin loaders.
• Eight /sdd-* workflows (overview, setup, specify, plan, compile, architecture-update,
  lifecycle, style-update) as shared skills.
• Path-scoped rules (constitution, memory-bank, repo-docs, specs), Memory Bank seed files,
  spec lifecycle folders (backlog/, active/, done/), Copilot agent persona, MIT
  license.

Fixed

• Interop matrix corrected against current VS Code documentation.
• Rule duplication removed so the single-source promise holds.
• .gitignore for local agent configuration.

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Retroactive release — tagged 2026-08-26 to version the pre-release history. Original date: 2026-08-03.