parallel-feature-development

Parallel Feature Development

Strategies for decomposing features into parallel work streams, establishing file ownership boundaries, avoiding conflicts, and integrating results from multiple implementer agents.

When to Use This Skill

• Decomposing a feature for parallel implementation
• Establishing file ownership boundaries between agents
• Designing interface contracts between parallel work streams
• Choosing integration strategies (vertical slice vs horizontal layer)
• Managing branch and merge workflows for parallel development

File Ownership Strategies

By Directory

Assign each implementer ownership of specific directories:

implementer-1: src/components/auth/
implementer-2: src/api/auth/
implementer-3: tests/auth/

Best for: Well-organized codebases with clear directory boundaries.

By Module

Assign ownership of logical modules (which may span directories):

implementer-1: Authentication module (login, register, logout)
implementer-2: Authorization module (roles, permissions, guards)

Best for: Feature-oriented architectures, domain-driven design.

By Layer

Assign ownership of architectural layers:

implementer-1: UI layer (components, styles, layouts)
implementer-2: Business logic layer (services, validators)
implementer-3: Data layer (models, repositories, migrations)

Best for: Traditional MVC/layered architectures.

Conflict Avoidance Rules

The Cardinal Rule

One owner per file. No file should be assigned to multiple implementers.

When Files Must Be Shared

If a file genuinely needs changes from multiple implementers:

1. Designate a single owner — One implementer owns the file
2. Other implementers request changes — Message the owner with specific change requests
3. Owner applies changes sequentially — Prevents merge conflicts
4. Alternative: Extract interfaces — Create a separate interface file that the non-owner can import without modifying

Interface Contracts