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+# SDLC Pipeline Diagram
+
+## Full Lifecycle
+
+```mermaid
+flowchart TD
+    subgraph Origin["Task Origin"]
+        GH["GitHub Issue"]
+        PP["Paperclip Issue"]
+    end
+
+    subgraph Approval["Board Gate"]
+        BA{"Board Approval<br/>Required?"}
+        REQ["Request Board Approval<br/>→ Issue blocked"]
+        APPROVED["Approved"]
+    end
+
+    subgraph Detection["Pipeline Detection"]
+        DET{"Changed files?"}
+        PA["Pipeline A<br/>Plugin / Feature"]
+        PB["Pipeline B<br/>Infrastructure"]
+    end
+
+    subgraph PipelineA["Pipeline A: Plugin / Feature Changes"]
+        direction TB
+        A_ENG["Engineer writes code<br/>(Gandalf)"]
+        A_PR["Create PR → main<br/>cc @cpfarhood"]
+        A_CI{"CI Passes?"}
+        A_UAT["UAT Review<br/>(Pixel Patty)<br/>E2E browser testing"]
+        A_UAT_PASS{"UAT Approved?"}
+        A_QA["QA Review<br/>(Regression Regina)<br/>Test coverage, regressions"]
+        A_QA_PASS{"QA Approved?"}
+        A_CTO["CTO Review<br/>(Null Pointer Nancy)<br/>Architecture, security"]
+        A_CTO_PASS{"CTO Approved?"}
+        A_CEO["CEO Merge<br/>(Countess)"]
+    end
+
+    subgraph PipelineB["Pipeline B: Infrastructure Changes"]
+        direction TB
+        B_ENG["Engineer writes code<br/>(Gandalf / Hugh)"]
+        B_PR["Create PR → main<br/>cc @cpfarhood"]
+        B_CI{"CI Passes?"}
+        B_QA["QA Review<br/>(Regression Regina)"]
+        B_QA_PASS{"QA Approved?"}
+        B_CTO["CTO Review<br/>(Null Pointer Nancy)"]
+        B_CTO_PASS{"CTO Approved?"}
+        B_CEO["CEO Merge<br/>(Countess)"]
+    end
+
+    subgraph Result["Outcome"]
+        MERGED["Merged to main<br/>✓ Production"]
+        RETURNED["Returned to Engineer<br/>Fix and resubmit"]
+    end
+
+    %% Origin routing
+    GH --> BA
+    PP --> DET
+    BA -->|"originKind: github"| REQ
+    REQ -->|"PAPERCLIP_APPROVAL_STATUS"| APPROVED
+    BA -->|"originKind: other"| DET
+    APPROVED --> DET
+
+    %% Pipeline detection
+    DET -->|"headlamp-*-plugin/ code"| PA
+    DET -->|".github/, infra/, org/"| PB
+
+    %% Pipeline A flow
+    PA --> A_ENG --> A_PR --> A_CI
+    A_CI -->|"Pass"| A_UAT
+    A_CI -->|"Fail"| RETURNED
+    A_UAT --> A_UAT_PASS
+    A_UAT_PASS -->|"Pass"| A_QA
+    A_UAT_PASS -->|"Fail"| RETURNED
+    A_QA --> A_QA_PASS
+    A_QA_PASS -->|"Pass"| A_CTO
+    A_QA_PASS -->|"Fail"| RETURNED
+    A_CTO --> A_CTO_PASS
+    A_CTO_PASS -->|"Pass"| A_CEO
+    A_CTO_PASS -->|"Fail — CEO rejection"| A_CTO
+    A_CTO_PASS -->|"Fail — other"| RETURNED
+    A_CEO --> MERGED
+
+    %% Pipeline B flow
+    PB --> B_ENG --> B_PR --> B_CI
+    B_CI -->|"Pass"| B_QA
+    B_CI -->|"Fail"| RETURNED
+    B_QA --> B_QA_PASS
+    B_QA_PASS -->|"Pass"| B_CTO
+    B_QA_PASS -->|"Fail"| RETURNED
+    B_CTO --> B_CTO_PASS
+    B_CTO_PASS -->|"Pass"| B_CEO
+    B_CTO_PASS -->|"Fail — CEO rejection"| B_CTO
+    B_CTO_PASS -->|"Fail — other"| RETURNED
+    B_CEO --> MERGED
+
+    RETURNED -->|"Fix and resubmit"| A_PR
+    RETURNED -->|"Fix and resubmit"| B_PR
+
+    %% Styling
+    classDef gate fill:#f9e4e4,stroke:#c0392b,color:#000
+    classDef pass fill:#e4f9e4,stroke:#27ae60,color:#000
+    classDef agent fill:#e4e9f9,stroke:#2980b9,color:#000
+    classDef decision fill:#fef9e7,stroke:#f39c12,color:#000
+
+    class BA,A_CI,A_UAT_PASS,A_QA_PASS,A_CTO_PASS,B_CI,B_QA_PASS,B_CTO_PASS,DET decision
+    class A_UAT,A_QA,A_CTO,B_QA,B_CTO gate
+    class MERGED pass
+    class A_ENG,B_ENG,A_CEO,B_CEO agent
+```
+
+## PR Review SLA
+
+```mermaid
+gantt
+    title PR Review SLA Timeline (per stage)
+    dateFormat X
+    axisFormat %d h
+
+    section SLA Windows
+    Normal review window   :done, 0, 24
+    CEO escalation at 24h  :active, 24, 48
+    SLA violation at 48h   :crit, 48, 72
+    Release blocker at 72h :crit, 72, 96
+```
+
+## Handoff Protocol
+
+```mermaid
+sequenceDiagram
+    participant Src as Source Agent
+    participant API as Paperclip API
+    participant Tgt as Target Agent
+
+    Src->>API: PATCH /issues/{id}<br/>assigneeAgentId: target
+    Src->>API: PATCH /issues/{id}<br/>status: "todo"
+    Note over Src,API: Never use "in_review" —<br/>it won't trigger inbox
+    Src->>API: POST /issues/{id}/release<br/>X-Paperclip-Run-Id header
+    API-->>Tgt: Inbox wake
+    Tgt->>API: POST /issues/{id}/checkout
+    Tgt->>Tgt: Begin work
+```
+
+## Issue Status Lifecycle
+
+```mermaid
+stateDiagram-v2
+    [*] --> backlog: Created (unscheduled)
+    [*] --> todo: Created (ready)
+    backlog --> todo: Scheduled
+    todo --> in_progress: Checkout
+    in_progress --> in_review: Awaiting feedback
+    in_progress --> blocked: External blocker
+    in_progress --> done: Work complete
+    in_review --> in_progress: Feedback received
+    blocked --> in_progress: Unblocked
+    in_progress --> cancelled: Abandoned
+    todo --> cancelled: Abandoned
+    backlog --> cancelled: Abandoned
+```