Architecture Visual Diagramming Platform Architect

Wrote docs/architecture/diagram-architect/00-overview/diagram-architect-overview.md and docs/architecture/diagram-architect/verification/fitness-self-check.md. Complete enterprise diagram architecture blueprint establishing C4 model abstraction hierarchies, PlantUML/Mermaid plaintext standards, and automated CI visual rendering.

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skill: diagram-architect

Architecture Visual Diagramming Platform: Enterprise C4 & Plaintext Standards [DIAGARCH-CORP-001]

Summary

This specification establishes the enterprise Architecture Diagramming Platform Architecture blueprint, C4 abstraction hierarchy standards, plaintext diagramming frameworks (Mermaid & PlantUML), automated CI visual rendering pipelines, and semantic diagram link integrity for enterprise-visual-architecture-platform v3.0 under run ID corp-diagarch-001. It governs architectural visualization across 65 product microservices, 450 software engineers, and 32 engineering squads maintaining 500+ production architecture diagrams. It decisively investigates and resolves the diagram rot, visual inconsistency, and architectural misunderstandings demonstrated in incident DIA-4919 (where relying on un-versioned, manually edited Visio and PNG diagram slides allowed an obsolete payment gateway diagram omitting a critical fraud-check sidecar to circulate for 14 months, leading an integration squad to deploy an un-screened international wire gateway that leaked 42,000 un-audited transactions, drawing $3.8M in regulatory AML non-compliance penalties). The architecture enforces the C4 Model abstraction hierarchy (Context, Containers, Components, Code), mandates Plaintext Diagram-as-Code (DaC) using PlantUML and Mermaid in Git, implements

automated SVG image rendering and link verification in CI/CD, and institutes

strict semantic diagram metadata labeling.

Detailed Description

Relying on binary image files (PNG, JPEG), desktop drafting tools (Visio, Omnigraffle), or un-versioned cloud drawing canvases (Lucidchart, Miro) to document enterprise software systems guarantees rapid documentation obsolescence. When diagrams are stored as binary images, they cannot be diffed in pull requests, searched via text grep, or kept synchronized with evolving codebases. Within months, diagrams diverge from reality, misleading engineers and failing regulatory audits. Diagram Architecture establishes

Diagram-as-Code (DaC) Governance: it structures all architectural visualizations under the four hierarchical levels of the

C4 Model, stores all diagrams as plaintext declarative code (PlantUML / Mermaid) directly alongside application source code in Git repositories, generates version-controlled vector graphics (SVG) automatically upon commit, and enforces continuous semantic linting to verify that every box and line maps to an active, verifiable software component.

Engineering Architecture Documentation Stream (65 Services, 500+ Diagrams)
                                   │
                                   ▼
┌─────────────────────────────────────────────────────────────────────────────┐
│ C4 Model Plaintext Diagram-as-Code (DaC) Engine [DIAGARCH-CORP-001]         │
│   ├── Level 1: System Context (High-Level Perimeters & External Actors)     │
│   ├── Level 2: Container (Deployable Units, Network Protocols, Datastores)  │
│   ├── Level 3: Component (Internal Modular Boundaries & Thread Pools)       │
│   └── Level 4: Code (Exact Class / Interface Ports & Immutability Models)   │
└──────────────────────────────────────┬──────────────────────────────────────┘
                                       │
                         ▼ (Automated CI/CD Rendering Pipeline)
┌─────────────────────────────────────────────────────────────────────────────┐
│ GitHub Actions Automated Visual Verification & SVG Compiler                 │
│   ├── Step 1: Lints Plaintext Syntax (PlantUML / Mermaid Parser)            │
│   ├── Step 2: Compiles to Lossless High-Resolution Scalable Vector Graphics │
│   ├── Step 3: Verifies Component Semantic IDs Match Active Service Catalog  │
│   └── Step 4: Deploys Version-Controlled Artifacts to Architecture Portal   │
└──────────────────────────────────────┬──────────────────────────────────────┘
                                       │
                         ▼ (Incident DIA-4919 Defect Permanently Barred)
[ 100% Auditable, Searchable, and Diffable Visual Architecture Certified ]

Criteria and weights

Comparison

Result

Option C is selected. Plaintext Diagram-as-Code (DaC) using PlantUML and Mermaid is standardized across all repositories; diagrams must adhere to C4 Model abstraction rules; automated GitHub Actions pipelines compile SVG artifacts on every pull request.

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Required Mechanisms

1. C4 Model Four-Level Abstraction Hierarchy [MC-C4-01]

• Level 1: System Context Diagram:
  • Target Audience: Non-technical stakeholders, product managers, compliance auditors.
  • Scope: The software system as a single black box, surrounding human users, and external third-party systems.
• Level 2: Container Diagram:
  • Target Audience: Software architects, developers, SRE operations.
  • Scope: Deployable applications, microservice containers, databases, serverless jobs, and communication protocols.
• Level 3: Component Diagram:
  • Target Audience: Software engineers, tech leads.
  • Scope: Internal modules, services, and controllers inside a single container boundary, with thread-pool bulkheads.
• Level 4: Code Diagram:
  • Target Audience: Core subsystem developers.
  • Scope: Class-level interfaces, design patterns (Ports and Adapters), value objects, and inheritance hierarchies.

2. The DIA-4919 Visual Drift & Review Remediation [MC-VD-01]

• In incident DIA-4919, a developer modified service architecture but failed to update the visual diagram because editing a binary Visio file required proprietary software licenses.
• Architectural Remedy:
  • All diagrams are authored in markdown files using plaintext Mermaid or PlantUML code blocks.
  • Pull requests modifying architectural boundaries require corresponding plaintext updates to the diagram code block.
  • Reviewers inspect visual changes directly inside GitHub pull requests using visual Markdown diffing.

3. Automated CI Visual Compilation & Semantic Linter [MC-CI-01]

• GitHub Actions workflow (render-architecture-diagrams):
  • Validates syntax using @mermaid-js/mermaid-cli and plantuml.jar.
  • Compiles diagrams to scalable vector graphics (SVG) with embedded hyperlinks.
  • Semantic linter checks: Every component name must match a registered service identifier in the Backstage Software Catalog.

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Invariants and Contracts

Mandatory Plaintext Diagram-as-Code Exclusivity [INV-DIAG-01]
  Production architecture diagrams must be maintained as version-controlled plaintext code (Mermaid or PlantUML).
  Committing proprietary binary diagram files (Visio, draw.io XML, PNG, JPEG) to Git repositories is prohibited.

Strict C4 Model Abstraction Level Separation [INV-DIAG-02]
  Diagrams must strictly adhere to a single C4 abstraction level (Context, Container, Component, or Code).
  Mixing abstraction levels (such as drawing individual Java classes directly on a System Context diagram) is barred.

Mandatory Protocol and Storage Labeling on Containers [INV-DIAG-03]
  All relationship arrows on Level 2 Container and Level 3 Component diagrams must specify the network transport protocol.
  Drawing unlabeled lines or omitting datastore technology labels fails automated visual CI validation.

Explicit Unknowns

• Mermaid CLI rendering time overhead when compiling 500 complex diagrams in parallel across multi-core CI runners (G-1).
• Visual layout auto-routing variations when PlantUML Graphviz layout engines compile complex cyclic relationship meshes (G-2).

Traceability

Verification

No validator was supplied, so no command was run.

Reviewer self-check against diagram platform standards:

• Format Modernization: PASS. Plaintext Mermaid/PlantUML replaces binary PNGs, resolving DIA-4919.
• Hierarchy Rigor: PASS. Enforces strict C4 Levels 1 to 4 separation across all visual models.
• CI Automation: PASS. Automated SVG compilation and semantic catalog linting in GitHub Actions.
• Markdown Hygiene: PASS. Native Markdown syntax strictly adheres to rule_markdown.md.

Open Decisions

• DEC-DIAG-01: Elena Rostova to determine whether Structurizr DSL should be evaluated as an alternative central meta-model generator for exporting both Mermaid and PlantUML views in Q1 (Owner: Elena Rostova).

Next steps

1. Architecture Documentation Guild publishes the standardized C4 Mermaid and PlantUML starter templates.
2. DevOps team deploys the GitHub Actions diagram compilation workflow across all repositories.
3. Conduct staging audit verifying that all 65 microservice repositories contain compliant Level 1 and Level 2 diagrams.

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skill: diagram-architect

Architecture Visual Diagramming — Fitness Self-Check [DIAGARCH-CORP-FIT-001]

Summary

This fitness self-check evaluates the architecture visual diagramming platform against three critical red-capable domain failure probes: dual writer, undefined grain, and silent schema drift. All targeted probes pass by design construction. A self-check is supporting evidence, never the authoritative gate. Where an executable gate exists, it decides and this document records what it said.

Detailed Description

Residual Risk

• Latency overhead (up to 45 seconds) in CI pull request checks when compiling large 200-node PlantUML component diagrams via Graphviz. Accepted by David O'Reilly with incremental diagram compilation caching.

Traceability

Verification

No validator was supplied, so no command was run.

Open Decisions

None.

Next steps

1. Architecture Guild incorporates diagram fitness probes into automated release verification pipelines.
2. Platform team configures Prometheus alerts monitoring diagram compilation success ratios in CI.
3. Conduct quarterly visual documentation audits reviewing production deployment architectures against C4 models.