Cursor vs FusionComparisonUpdated 2026-03-16
SUMMARY
Cursor (IDE) uses mdc 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
| Feature | Cursor | Fusion |
|---|---|---|
| Config format | mdc | mdc |
| Hierarchy support | ✓ | ✗ |
| Global config | ✓ | ✗ |
| Project config | ✓ | ✓ |
| Subdirectory scoping | ✓ | ✗ |
| File inclusion / imports | ✗ | ✗ |
| Ignore file | .cursorignore | ✗ |
| IDE integration | ✓ | ✓ |
| Schema / structure | Hybrid (MDC frontmatter + Markdown) | Hybrid (MDC frontmatter + Markdown) |
| Git committed | ✓ | ✓ |
| Encoding | UTF-8 | UTF-8 |
FILE MAPPING
| Purpose | Cursor | Fusion |
|---|---|---|
| Project rules | .cursor/rules/*.mdc | .builder/rules/*.mdc |
| Project rules | AGENTS.md | .builderrules |
SIDE-BY-SIDE CODE SAMPLES
Cursor
.cursor/rules/*.mdc
mdc
---
description: React component conventions and patterns
globs: "*.tsx"
alwaysApply: false
---
# React Component Rules
- Use functional components with explicit return types
- Define props interface directly above the component
- Export components as named exports, never default
- Use Tailwind CSS utility classes exclusively
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
Cursor: Supported. Fusion: Not supported.
Cursor: Supported. Fusion: Not supported.
Cursor: Supported. Fusion: Not supported.
Cursor: .cursorignore. Fusion: Not supported.
WHICH SHOULD I USE?
Choose based on your IDE/CLI preference. If you use Cursor, configure .cursorrules. 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
File references:
agentconfig.ing2026-03-16COMPARE(1)