Cross-Layer Check

Check if your changes considered all dimensions. Most bugs come from "didn't think of it", not lack of technical skill.

Note: This is a post-implementation safety net. Ideally, read the Pre-Implementation Checklist before writing code.

Related Documents

Execution Steps

1. Identify Change Scope

git status
git diff --name-only

2. Select Applicable Check Dimensions

Based on your change type, execute relevant checks below:

Dimension A: Cross-Layer Data Flow (Required when 3+ layers)

Trigger: Changes involve 3 or more layers

Checklist:

• • Read flow: Database -> Service -> API -> UI
• • Write flow: UI -> API -> Service -> Database
• • Types/schemas correctly passed between layers?
• • Errors properly propagated to caller?
• • Loading/pending states handled at each layer?

Detailed Guide: .trellis/spec/guides/cross-layer-thinking-guide.md

Dimension B: Code Reuse (Required when modifying constants/config)

Trigger:

• •Modifying UI constants (label, icon, color)
• •Modifying any hardcoded value
• •Seeing similar code in multiple places
• •Creating a new utility/helper function
• •Just finished batch modifications across files

Checklist:

• • Search first: How many places define this value?
  bash

  # Search in source files (adjust extensions for your project)
  grep -r "value-to-change" src/
  

• • If 2+ places define same value -> Should extract to shared constant
• • After modification, all usage sites updated?
• • If creating utility: Does similar utility already exist?

Detailed Guide: .trellis/spec/guides/code-reuse-thinking-guide.md

Dimension B2: New Utility Functions

Trigger: About to create a new utility/helper function

Checklist:

• • Search for existing similar utilities first
  bash

  grep -r "functionNamePattern" src/
  

• • If similar exists, can you extend it instead?
• • If creating new, is it in the right location (shared vs domain-specific)?

Dimension B3: After Batch Modifications

Trigger: Just modified similar patterns in multiple files

Checklist:

• • Did you check ALL files with similar patterns?
  bash

  grep -r "patternYouChanged" src/
  

• • Any files missed that should also be updated?
• • Should this pattern be abstracted to prevent future duplication?

Dimension C: Import/Dependency Paths (Required when creating new files)

Trigger: Creating new source files

Checklist:

• • Using correct import paths (relative vs absolute)?
• • No circular dependencies?
• • Consistent with project's module organization?

Dimension D: Same-Layer Consistency

Trigger:

• •Modifying display logic or formatting
• •Same domain concept used in multiple places

Checklist:

• • Search for other places using same concept
  bash

  grep -r "ConceptName" src/
  

• • Are these usages consistent?
• • Should they share configuration/constants?

Common Issues Quick Reference

Output

Report:

1. •Which dimensions your changes involve
2. •Check results for each dimension
3. •Issues found and fix suggestions