ZAIXOS Engineering Platform — Implementation Phase Plan

Document type: Extraction Planning Specification
Version: 1.0 · Phase: 12-4
Status: Permanent execution authority — planning only for 12-5–12-9

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Purpose

Plan execution of Phases 12-5 through 12-9 without performing implementation in Phase 12-4.

Each phase: objective, inputs, outputs, gates, rollback, Format B report required.

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Migration timeline (summary)

Phase	Title	Duration estimate	Depends on
12-5	Repository Scaffold	1 phase	12-4 complete
12-6	Platform Extraction	2–4 phases (waves)	12-5
12-7	Consumer Migration	1–2 phases	12-6 rc.final
12-8	Platform Validation	1 phase	12-7
12-9	Platform GA Freeze	1 phase	12-8

Estimates are planning guides — not schedule commitments.

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Phase 12-5 — Repository Scaffold

Objective

Create empty zaixos-engineering-platform repository matching REPOSITORY_LAYOUT_PLAN.md.

Inputs

• Layout plan
• Package architecture
• PRE-* baseline from Dental Clinic

Outputs

• Empty directory tree
• composer.json skeleton
• phpunit.xml.dist
• CI workflow stubs (no tests yet)
• README pointing to planning docs

Gates (SC-*)

All VALIDATION_PLAN.md SC-1–SC-5.

Rollback

ROLLBACK_PLAN.md RB-12-5.

Explicitly NOT in 12-5

• Asset copy from Dental Clinic
• Packagist publish
• Product composer changes

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Phase 12-6 — Platform Extraction

Objective

Copy all platform assets to platform repo per EXTRACTION_SEQUENCE.md waves W1–W8.

Inputs

• 12-5 scaffold
• Dental Clinic RP-0 baseline SHA
• MIGRATION_MATRIX.md

Outputs

• Platform repo with full content
• 1.0.0-rc.final candidate
• Platform CI green (EX-W6)
• Updated adapter manifest.json paths per PACKAGE_SPLIT_PLAN.md

Wave execution order

W1 → W2 → W3 → W4 → W5 → W6 → W7 → W8 (strict).

Gates

EX-W1 through EX-W8 per VALIDATION_PLAN.md.

Rollback

RB-12-6 — Dental Clinic untouched.

Explicitly NOT in 12-6

• Dental Clinic composer require
• Embedded deletion
• contract obligation changes

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Phase 12-7 — Consumer Migration

Objective

Dental Clinic becomes platform consumer #1 per CONSUMER_INTEGRATION_PLAN.md.

Inputs

• Platform 1.0.0-rc.final
• Consumer integration plan
• PLATFORM_CONFIGURATION_REFERENCE.md

Outputs

• composer.json require
• .zaixos/platform.yml, platform.lock
• Materialized adapter + .cursor/ mount
• Product CI wired to vendor validation tests
• Dual-run state (embedded + vendored)

Gates

CO-1 through CO-6 per validation plan.

Rollback

RB-12-7 — restore embedded authoritative mode.

Explicitly NOT in 12-7

• Remove embedded ERP docs
• Platform GA tag
• Packagist public GA (rc publish OK)

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Phase 12-8 — Platform Validation

Objective

Prove parity, consumer correctness, and compatibility per VALIDATION_PLAN.md PV-*.

Inputs

• 12-7 dual-run state
• Baseline checksums RP-0, RP-3

Outputs

• Signed validation report (Format B)
• Architect acceptance for GA readiness
• No version bump unless fixes require rc bump

Gates

PV-1 through PV-8 + KPI measurements.

Rollback

RB-12-8 — return to 12-7 fix forward or RB-12-7.

Explicitly NOT in 12-8

• Embedded deletion
• Platform 1.0.0 GA tag (prepare only)

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Phase 12-9 — Platform GA Freeze

Objective

Release zaixos-platform@v1.0.0; sunset embedded copies; declare ZEP GA.

Inputs

• 12-8 acceptance
• RELEASE_PLAN.md R4 artifacts

Outputs

• Platform tag zaixos-platform@v1.0.0
• Packagist publish
• Embedded ERP removed from Dental Clinic (stub README)
• Product platform.lock @ 1.0.0 exact
• KPI-10 = 0
• Phase Format B + Architect RESPONSE_TEMPLATE

Gates

GA-1 through GA-5 per validation plan.

Rollback

RB-12-9 (within support window) — requires RP-0 archive.

Git freeze

Developer executes per GIT_FREEZE_PROCEDURE — platform repo tag + product release doc.

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Cross-phase documentation requirements

Each phase MUST produce:

Deliverable	Format
Phase report	Format B
Updated restore point	RP-* ID
Validation evidence	Test output / checksum
Architect acceptance	RESPONSE_TEMPLATE (12-7, 12-8, 12-9)

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Decision freeze

Phase 12-4 finalizes all planning decisions required for 12-5:

• Repository name: zaixos-engineering-platform
• Package name: zaixos/engineering-platform
• Extraction waves W1–W8 order
• Consumer #1: Dental Clinic ROS
• GA version: 1.0.0 / contracts@1
• No additional planning artifacts required before 12-5

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Implementation Phase Plan v1.0 — Phase 12-4.