Amazon Q Developer vs FusionUpdated 2026-03-16

SUMMARY

Amazon Q Developer (CLI) uses markdown configuration while Fusion (IDE) uses mdc. They differ on 4 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.

FEATURE COMPARISON

FeatureAmazon Q DeveloperFusion
Config formatmarkdownmdc
Hierarchy support
Global config
Project config
Subdirectory scoping
File inclusion / imports
Ignore file
IDE integrationCLI
Schema / structureFree-form (Markdown)Hybrid (MDC frontmatter + Markdown)
Git committed
EncodingUTF-8UTF-8

FILE MAPPING

PurposeAmazon Q DeveloperFusion
Project rules.amazonq/rules/*.md.builder/rules/*.mdc

SIDE-BY-SIDE CODE SAMPLES

Amazon Q Developer
.amazonq/rules/*.md
markdown
# React Component Standards

## Purpose
Ensure consistent React component patterns across the frontend codebase.

## Priority
High

## Instructions
- Use functional components with TypeScript
- Define props interfaces above the component
- Use React.FC only when children are expected
- Colocate styles using CSS Modules (*.module.css)
- Extract hooks into separate files when reused
- Memoize expensive computations with useMemo
- Use React.lazy for route-level code splitting

Fusion
.builder/rules/*.mdc
mdc
---
description: React component conventions
globs: src/components/**/*.tsx
alwaysApply: false
---

# React Component Rules

## Structure
- Use functional components with TypeScript
- Define props interface above the component
- Export components as named exports

## Styling
- Use the project design system tokens for spacing and colors
- Prefer utility classes over custom CSS
- Keep component-specific styles colocated

## Patterns
- Wrap async data in Suspense boundaries
- Use forwardRef for reusable interactive components
- Keep components under 150 lines; extract hooks for logic

## Accessibility
- All interactive elements need aria-labels
- Use semantic HTML elements (nav, main, section)
- Ensure keyboard navigation works for custom widgets

KEY DIFFERENCES

1. Config format

Amazon Q Developer: markdown. Fusion: mdc.

2. Global config

Amazon Q Developer: Supported. Fusion: Not supported.

3. IDE integration

Amazon Q Developer: CLI. Fusion: Supported.

4. Schema / structure

Amazon Q Developer: Free-form (Markdown). Fusion: Hybrid (MDC frontmatter + Markdown).

WHICH SHOULD I USE?

Recommendation

Choose based on your IDE/CLI preference. If you use Amazon Q Developer, configure .amazonq/rules/*.md. If you use Fusion, configure .builder/rules/*.mdc. Many projects include config files for multiple tools so each team member can use their preferred editor.

PORTABILITY TIP

sync-instructions.sh
bash
# Maintain a single source of truth:
cp AI-INSTRUCTIONS.md CLAUDE.md
cp AI-INSTRUCTIONS.md .cursorrules
cp AI-INSTRUCTIONS.md AGENTS.md

SEE ALSO

agentconfig.ing2026-03-16COMPARE(1)