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roadcrew_template_type: "memory-bank"
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roadcrew_last_updated: "2025-11-03"
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roadcrew_license: "See LICENSE file in .roadcrew folder"
roadcrew_copyright: "Copyright (c) 2025 North Star Holdings, LLC"
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cline_memory_bank: "systemPatterns"
---

# System Patterns

**System architecture, key technical decisions, design patterns in use, component relationships, and critical implementation paths**

Last Updated: {{LAST_UPDATED}}  
Architecture Version: {{ARCHITECTURE_VERSION}}

---

## Architecture Overview

### High-Level System Architecture

{{ARCHITECTURE_OVERVIEW}}

### System Layers

{{SYSTEM_LAYERS}}

### Component Diagram

```
{{ARCHITECTURE_DIAGRAM}}
```

**Legend:**
- {{DIAGRAM_ELEMENT_1}}
- {{DIAGRAM_ELEMENT_2}}
- {{DIAGRAM_ELEMENT_3}}

---

## Key Technical Decisions

### Decision 1: {{DECISION_1_TOPIC}}

**Context:**
{{DECISION_1_CONTEXT}}

**Decision:**
{{DECISION_1_WHAT}}

**Rationale:**
{{DECISION_1_WHY}}

**Alternatives Considered:**
- {{DECISION_1_ALT_1}}
- {{DECISION_1_ALT_2}}

**Consequences:**
{{DECISION_1_CONSEQUENCES}}

---

### Decision 2: {{DECISION_2_TOPIC}}

**Context:**
{{DECISION_2_CONTEXT}}

**Decision:**
{{DECISION_2_WHAT}}

**Rationale:**
{{DECISION_2_WHY}}

**Alternatives Considered:**
- {{DECISION_2_ALT_1}}
- {{DECISION_2_ALT_2}}

**Consequences:**
{{DECISION_2_CONSEQUENCES}}

---

### Decision 3: {{DECISION_3_TOPIC}}

**Context:**
{{DECISION_3_CONTEXT}}

**Decision:**
{{DECISION_3_WHAT}}

**Rationale:**
{{DECISION_3_WHY}}

**Alternatives Considered:**
- {{DECISION_3_ALT_1}}
- {{DECISION_3_ALT_2}}

**Consequences:**
{{DECISION_3_CONSEQUENCES}}

---

## Design Patterns In Use

### Pattern 1: {{PATTERN_1_NAME}}

**Where used:**
- {{PATTERN_1_COMPONENT_1}}
- {{PATTERN_1_COMPONENT_2}}
- {{PATTERN_1_COMPONENT_3}}

**Purpose:**
{{PATTERN_1_PURPOSE}}

**Implementation notes:**
- {{PATTERN_1_NOTE_1}}
- {{PATTERN_1_NOTE_2}}

**Example:**
```
{{PATTERN_1_EXAMPLE}}
```

---

### Pattern 2: {{PATTERN_2_NAME}}

**Where used:**
- {{PATTERN_2_COMPONENT_1}}
- {{PATTERN_2_COMPONENT_2}}

**Purpose:**
{{PATTERN_2_PURPOSE}}

**Implementation notes:**
- {{PATTERN_2_NOTE_1}}
- {{PATTERN_2_NOTE_2}}

**Example:**
```
{{PATTERN_2_EXAMPLE}}
```

---

### Pattern 3: {{PATTERN_3_NAME}}

**Where used:**
- {{PATTERN_3_COMPONENT_1}}
- {{PATTERN_3_COMPONENT_2}}

**Purpose:**
{{PATTERN_3_PURPOSE}}

**Implementation notes:**
- {{PATTERN_3_NOTE_1}}
- {{PATTERN_3_NOTE_2}}

**Example:**
```
{{PATTERN_3_EXAMPLE}}
```

---

## Component Relationships

### Component A: {{COMPONENT_A_NAME}}

**Depends on:**
- {{COMPONENT_A_DEP_1}}
- {{COMPONENT_A_DEP_2}}

**Used by:**
- {{COMPONENT_A_USER_1}}
- {{COMPONENT_A_USER_2}}

**Responsibilities:**
- {{COMPONENT_A_RESP_1}}
- {{COMPONENT_A_RESP_2}}
- {{COMPONENT_A_RESP_3}}

**Key methods/exports:**
- {{COMPONENT_A_METHOD_1}}
- {{COMPONENT_A_METHOD_2}}

---

### Component B: {{COMPONENT_B_NAME}}

**Depends on:**
- {{COMPONENT_B_DEP_1}}
- {{COMPONENT_B_DEP_2}}

**Used by:**
- {{COMPONENT_B_USER_1}}
- {{COMPONENT_B_USER_2}}

**Responsibilities:**
- {{COMPONENT_B_RESP_1}}
- {{COMPONENT_B_RESP_2}}
- {{COMPONENT_B_RESP_3}}

**Key methods/exports:**
- {{COMPONENT_B_METHOD_1}}
- {{COMPONENT_B_METHOD_2}}

---

### Component C: {{COMPONENT_C_NAME}}

**Depends on:**
- {{COMPONENT_C_DEP_1}}
- {{COMPONENT_C_DEP_2}}

**Used by:**
- {{COMPONENT_C_USER_1}}
- {{COMPONENT_C_USER_2}}

**Responsibilities:**
- {{COMPONENT_C_RESP_1}}
- {{COMPONENT_C_RESP_2}}
- {{COMPONENT_C_RESP_3}}

**Key methods/exports:**
- {{COMPONENT_C_METHOD_1}}
- {{COMPONENT_C_METHOD_2}}

---

## Critical Implementation Paths

### {{FLOW_1_NAME}}: {{FLOW_1_TITLE}}

**Purpose:** {{FLOW_1_PURPOSE}}

**Entry point:** {{FLOW_1_ENTRY}}

**Steps:**

1. {{FLOW_1_STEP_1}}
2. {{FLOW_1_STEP_2}}
3. {{FLOW_1_STEP_3}}
4. {{FLOW_1_STEP_4}}
5. {{FLOW_1_STEP_5}}

**Exit conditions:** {{FLOW_1_EXIT}}

**Error handling:** {{FLOW_1_ERROR_HANDLING}}

---

### {{FLOW_2_NAME}}: {{FLOW_2_TITLE}}

**Purpose:** {{FLOW_2_PURPOSE}}

**Entry point:** {{FLOW_2_ENTRY}}

**Steps:**

1. {{FLOW_2_STEP_1}}
2. {{FLOW_2_STEP_2}}
3. {{FLOW_2_STEP_3}}
4. {{FLOW_2_STEP_4}}

**Exit conditions:** {{FLOW_2_EXIT}}

**Error handling:** {{FLOW_2_ERROR_HANDLING}}

---

### {{FLOW_3_NAME}}: {{FLOW_3_TITLE}}

**Purpose:** {{FLOW_3_PURPOSE}}

**Entry point:** {{FLOW_3_ENTRY}}

**Steps:**

1. {{FLOW_3_STEP_1}}
2. {{FLOW_3_STEP_2}}
3. {{FLOW_3_STEP_3}}
4. {{FLOW_3_STEP_4}}
5. {{FLOW_3_STEP_5}}
6. {{FLOW_3_STEP_6}}

**Exit conditions:** {{FLOW_3_EXIT}}

**Error handling:** {{FLOW_3_ERROR_HANDLING}}

---

## Data Flow

### Input → Processing → Output

```
{{DATA_FLOW_DIAGRAM}}
```

**Key transformations:**
- {{DATA_FLOW_TRANSFORM_1}}
- {{DATA_FLOW_TRANSFORM_2}}
- {{DATA_FLOW_TRANSFORM_3}}

---

## Performance Considerations

### Bottlenecks & Optimizations

- {{BOTTLENECK_1}}: {{OPTIMIZATION_1}}
- {{BOTTLENECK_2}}: {{OPTIMIZATION_2}}
- {{BOTTLENECK_3}}: {{OPTIMIZATION_3}}

### Caching Strategy

{{CACHING_STRATEGY}}

### Scalability Notes

{{SCALABILITY_NOTES}}

---

## Related Documents

- **Project Brief:** See `projectbrief.md` for scope and requirements
- **Product Context:** See `productContext.md` for problems and UX goals
- **Tech Context:** See `techContext.md` for technology stack
- **Active Context:** See `activeContext.md` for current work
- **Progress:** See `progress.md` for status and milestones

---

**Note:** This document captures HOW the system is built. Reference this when implementing features, debugging issues, or planning architecture changes.