Junie vs WindsurfComparisonUpdated 2026-03-16
SUMMARY
Junie (Agent) uses markdown configuration while Windsurf (IDE) uses markdown. They differ on 5 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.
FEATURE COMPARISON
| Feature | Junie | Windsurf |
|---|---|---|
| Config format | markdown | markdown |
| Hierarchy support | ✗ | ✓ |
| Global config | ✗ | ✓ |
| Project config | ✓ | ✓ |
| Subdirectory scoping | ✗ | ✓ |
| File inclusion / imports | ✗ | ✗ |
| Ignore file | ✗ | .codeiumignore |
| IDE integration | Agent | ✓ |
| Schema / structure | Free-form (Markdown) | Free-form (Markdown) |
| Git committed | ✓ | ✓ |
| Encoding | UTF-8 | UTF-8 |
SIDE-BY-SIDE CODE SAMPLES
Junie
.junie/guidelines.md
markdown
# Project Guidelines
## Language & Framework
- Kotlin with Spring Boot 3.x
- Gradle with Kotlin DSL
- JDK 21 with virtual threads
## Architecture
- Hexagonal architecture (ports & adapters)
- Domain events for cross-module communication
- CQRS for read-heavy endpoints
## Code Standards
- Follow Kotlin coding conventions
- Use data classes for DTOs
- Prefer sealed classes for domain errors
- Extension functions over utility classes
## Testing
- JUnit 5 with Kotest assertions
- Testcontainers for integration tests
- MockK for mocking (not Mockito)
## Build & Run
- Build: ./gradlew build
- Test: ./gradlew test
- Run: ./gradlew bootRun
Windsurf
.windsurf/rules/*.md
markdown
---
trigger: glob
globs: "**/*.test.ts"
---
# Testing Conventions
- Use Vitest as the test runner
- Colocate test files next to source files
- Use describe blocks organized by function/component name
- Prefer userEvent over fireEvent in component tests
- Mock external services; never hit real APIs in unit tests
KEY DIFFERENCES
Junie: Not supported. Windsurf: Supported.
Junie: Not supported. Windsurf: Supported.
Junie: Not supported. Windsurf: Supported.
Junie: Not supported. Windsurf: .codeiumignore.
Junie: Agent. Windsurf: Supported.
WHICH SHOULD I USE?
Choose based on your IDE/CLI preference. If you use Junie, configure .junie/guidelines.md. If you use Windsurf, configure .windsurfrules. 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)