SDLC blueprint

Spiral ceremonies → ceremony foundation

**Purpose:** Map **Spiral Model** quadrant events and anchor-point milestones to methodology-neutral **intent types** in [`ceremony-foundation.md`](ceremony-foundation.md).

Spiral ceremonies → ceremony foundation

Purpose: Map Spiral Model quadrant events and anchor-point milestones to methodology-neutral intent types in Ceremony foundation (methodology-neutral).

Canonical Spiral narrative: https://forgesdlc.com/methodologies-spiral.html · Wikipedia — Spiral model

Note: The Spiral Model's ceremonies revolve around quadrant transitions and milestone gates. Below maps typical practices; actual cadence depends on spiral scope and risk profile.


Practices / meetings × intent types

Common practice Foundation intents (primary → secondary) Notes
Spiral planning (Q1) C1 AlignC2 Commit Define objectives, alternatives, constraints; commit to risk-analysis approach.
Risk review (Q2) C6 AssureC1 Align Systematic risk identification and resolution; may redirect objectives.
Development sync (Q3) C3 Sync Coordination during build; approach may be Agile, phased, or prototype-driven.
Prototype demo C4 InspectC6 Assure Demonstrate risk-reduction evidence; validate feasibility.
Anchor-point review (Q4) C4 InspectC1 Align Stakeholder commitment gate; evaluate results and plan next spiral.
Retrospective C5 Improve Compare predicted vs actual risk outcomes; improve estimation and process.

C6 in the Spiral Model is primarily risk-driven: assurance comes from systematic risk analysis (Q2) and evidence-based reviews (Q4), not from a separate quality phase.


Tracking

Risk register is the primary tracking artifact beyond the standard spine. Each spiral should document: risks identified, resolution strategy chosen, outcome achieved. Git shows engineering progress; risk decisions need explicit documentation in docs/ or the project risk register.


Suggestions (Spiral-specific)

Practice Suggestions
Spiral planning Scale planning effort to the spiral: early concept spirals need hours, not days. Focus on what risks to address, not detailed task breakdowns.
Risk review Prioritize ruthlessly: address the top 3–5 risks per spiral. Use prototypes for technical risks, market research for business risks.
Prototype demo Make prototypes visibly disposable — label them, timebox them, and plan their retirement. Production-quality prototypes defeat the purpose.
Anchor-point review Present evidence, not opinions. Show what risks were resolved, what remains, and what the next spiral will address.
Retrospective Track risk prediction accuracy across spirals. Teams that consistently underestimate risk need to adjust their analysis approach.

Crosswalk to other methodologies: Methodology bridge — foundation intents ↔ named ceremonies.

Canonical source

Edit https://github.com/autowww/blueprints/blob/main/sdlc/methodologies/ceremonies/spiral.md first; regenerate with docs/build-handbook.py.