Handbook
Phased delivery (Waterfall-style and hybrids)
**Phased delivery** (often associated with **Waterfall**) sequences work through **distinct phases** — e.g. requirements → design → implementation → verification → release — with **gates** between pha
Phased delivery (Waterfall-style and hybrids)
What it is
Phased delivery (often associated with Waterfall) sequences work through distinct phases — e.g. requirements → design → implementation → verification → release — with gates between phases. Each phase produces approved artifacts before the next begins. This is common in regulated industries, hardware–software dependencies, fixed-price contracts, and safety-critical systems.
It contrasts with iterative Agile delivery: phases emphasize upfront baselines and change control over frequent increments.
Process diagram (handbook)
Sequential phases with gate approvals — names and formality vary; many orgs iterate inside a phase while keeping major baselines gated.
Authoritative sources (external)
| Resource | Executive summary (why it’s linked here) |
|---|---|
| ISO/IEC/IEEE 12207 | International standard for software life-cycle processes—formal anchor for phased/regulated delivery (catalogue; full text is paid/licensed). |
| Wikipedia — Waterfall model | Informal history and diagram of sequential phases—context, not a normative standard. |
| Wikipedia — Software development process | Waterfall as one lifecycle among many—helps compare with iterative approaches. |
| Wikipedia — Agile software development | Contrast between iterative Agile and plan-driven lifecycles—useful for hybrid (gates + iterations). |
Reality: Many organizations use hybrids: phased gates for compliance, iterative development within a phase.
Typical phases (illustrative)
| Phase | Typical outputs |
|---|---|
| Requirements | Specs, traceability, hazard analysis (if applicable). |
| Design | Architecture, interfaces, detailed design. |
| Implementation | Code, unit tests per standard. |
| Verification | Integration, system test, validation evidence. |
| Release | Release notes, sign-off, deployment package. |
Gates: formal reviews or approvals (often documented outside git). Git shows engineering activity; it does not replace signatures or baselines stored in a quality or ALM system.
Mapping to this blueprint’s SDLC
Software development lifecycle (SDLC) Phases A–F are already a lightweight lifecycle (discover → release). Phased delivery in the strict sense narrows parallel work: you may freeze requirements artifacts before bulk build, or require phase exit criteria per your standard.
| Strict phased idea | Blueprint alignment |
|---|---|
| Baselines | Versioned specs under docs/requirements/, change control (change.html). |
| Traceability | Requirements ↔ tests ↔ risks matrices. |
| Verification evidence | Test plans, CI reports, release checklist ([release docs in project]). |
Ceremonies: gates and reviews mapped to intent types — Phased delivery ceremonies → ceremony foundation · foundation.
Roles: how phased delivery emphasizes Steer & govern and Assure, and splits Build by handoffs—Roles, archetypes & methodology titles §1–5 and Methodology roll-up.
Agentic SDLC: phased + agents + tracking
| Topic | Guidance |
|---|---|
| Gates | Agent-generated code still passes human gate criteria (review, static analysis, required tests). |
| Phase attribution | Commits may touch multiple “phases” in file paths; work unit metadata (REQ id, phase tag) matters more than folder names. |
| Documentation | Agents can draft specs; approval remains a human/compliance step. |
| Tracking foundation | TRACKING-FOUNDATION supports milestone windows and phase labels on work units for reporting; approvals are out of band. |
Prescriptive deep dive (teams)
Package Phased delivery — deep-dive package (blueprint) — stages vs A–F, gate roles, ceremonies (charter, TRR, UAT, PIR), flow maps. Handbook: methodologies-phased-foundation.html through methodologies-phased-process.html.
Further reading
- Project
TRACKING-CHALLENGES.md— phased / Waterfall-oriented challenges - Companion: Scrum, Agentic SDLC
Canonical source
Edit https://github.com/autowww/blueprints/blob/main/sdlc/methodologies/phased-delivery.md first; regenerate with docs/build-handbook.py.