Dependency Mapping

Purpose

Identify and document dependencies between requirements to enable proper sequencing, impact analysis, and prevent blocked work during implementation.

When to Use

• After requirements documented
• Implementation planning
• Sprint planning
• Impact analysis
• Risk assessment

Prerequisites

• Requirements enumerated with IDs
• Requirements understood
• Technical context available

Process

Step 1: Identify Dependency Types

Dependency categories:
- Requires: REQ-A requires REQ-B to exist first
- Enhances: REQ-A enhances/extends REQ-B
- Conflicts: REQ-A conflicts with REQ-B
- Related: REQ-A and REQ-B share components
- External: REQ-A depends on external system

Step 2: Map Each Requirement

For each requirement:
1. What must exist before this can work?
2. What does this enable?
3. Are there shared components?
4. Are there conflicts?
5. External dependencies?

Step 3: Create Dependency Graph

Document as:
- Directed graph (A → B means A depends on B)
- Identify root nodes (no dependencies)
- Identify leaf nodes (nothing depends on them)
- Find critical paths
- Detect cycles (error!)

Step 4: Identify Implementation Order

Topological sort:
1. Implement root nodes first
2. Then nodes whose dependencies are met
3. Continue until all implemented
4. Flag parallel opportunities

Step 5: Document Dependency Matrix

Matrix format:
          | REQ-A | REQ-B | REQ-C |
REQ-A     |   -   |   →   |       |
REQ-B     |   ←   |   -   |   →   |
REQ-C     |       |   ←   |   -   |

→ = depends on
← = depended upon by

Inputs

Input	Type	Required	Description
requirements_spec	Markdown	Yes	All requirements
architecture	Markdown	Optional	Technical dependencies

Outputs

Output	Type	Description
dependency_map.json	JSON	Complete dependency data
dependency_graph.mermaid	Mermaid	Visual graph
implementation_order.md	Markdown	Suggested sequence

StudyAbroad-Specific Considerations

• Authentication is foundational (most features depend on it)
• University API must work before search features
• Profile must exist before application features
• GDPR features required across all data handling

Integration Points

• Orchestrator: Task sequencing
• Test Manager: Test order planning
• Architecture Agent: Technical dependency validation

Examples

Dependency Graph - StudyAbroad-v1

graph TD
    REQ-001[User Auth] --> REQ-002[Profile]
    REQ-001 --> REQ-003[Search]
    REQ-002 --> REQ-004[Application]
    REQ-003 --> REQ-004
    REQ-004 --> REQ-005[Documents]
    REQ-004 --> REQ-006[Tracking]
    REQ-001 --> REQ-010[GDPR Consent]
    REQ-002 --> REQ-011[Data Export]
    REQ-002 --> REQ-012[Account Delete]

Implementation Order:
1. REQ-001 (Auth) - Foundation
2. REQ-010 (GDPR Consent) - Required with auth
3. REQ-002 (Profile) - After auth
4. REQ-003 (Search) - After auth
5. REQ-011, REQ-012 (GDPR) - After profile
6. REQ-004 (Application) - After profile & search
7. REQ-005 (Documents) - After application
8. REQ-006 (Tracking) - After application

Parallel Opportunities:
- REQ-002 and REQ-003 can parallel after REQ-001
- REQ-005 and REQ-006 can parallel after REQ-004

Validation

• All requirements in dependency map
• No circular dependencies
• Root nodes identified
• Implementation order valid
• External dependencies flagged