JetBrains AI / Junie vs PearAIUpdated 2026-03-16

SUMMARY

JetBrains AI / Junie (IDE) uses markdown configuration while PearAI (Editor) uses markdown. They differ on 2 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.

FEATURE COMPARISON

FeatureJetBrains AI / JuniePearAI
Config formatmarkdownmarkdown
Hierarchy support
Global config
Project config
Subdirectory scoping
File inclusion / imports
Ignore file.aiignore
IDE integrationEditor
Schema / structureFree-form (Markdown)Free-form (Markdown)
Git committed
EncodingUTF-8UTF-8

FILE MAPPING

PurposeJetBrains AI / JuniePearAI
Project rules.aiassistant/rules/*.md.pearai/rules

SIDE-BY-SIDE CODE SAMPLES

JetBrains AI / Junie
.aiassistant/rules/*.md
markdown
# Kotlin Conventions

## Language Features
- Use Kotlin 2.x with coroutines for async work
- Prefer data classes for DTOs and value objects
- Use sealed classes/interfaces for domain errors
- Extension functions over utility classes

## Spring Boot
- Constructor injection (no field injection)
- Use @ConfigurationProperties over @Value
- Prefer WebFlux for reactive endpoints
- Use Spring Security with method-level security

## Testing
- JUnit 5 with Kotest assertions
- MockK for mocking (not Mockito)
- Testcontainers for integration tests
- Use @Nested for test organization

PearAI
.pearai/rules
markdown
# PearAI Project Rules

## Framework
- Next.js 15 App Router with TypeScript
- Drizzle ORM with PostgreSQL
- TailwindCSS v4 for styling

## Patterns
- Use server actions for mutations
- Colocate loading.tsx and error.tsx with page routes
- Prefer RSC; add "use client" only when needed

## Naming
- Components: PascalCase (UserProfile.tsx)
- Utilities: camelCase (formatDate.ts)
- Database tables: snake_case

## Dependencies
- Do NOT add new dependencies without asking
- Use date-fns for date manipulation
- Use zod for all validation

## Commands
- Dev: pnpm dev
- Build: pnpm build
- Lint: pnpm lint

KEY DIFFERENCES

1. Ignore file

JetBrains AI / Junie: .aiignore. PearAI: Not supported.

2. IDE integration

JetBrains AI / Junie: Supported. PearAI: Editor.

WHICH SHOULD I USE?

Recommendation

Choose based on your IDE/CLI preference. If you use JetBrains AI / Junie, configure .aiassistant/rules/*.md. If you use PearAI, configure .pearai/rules. 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)