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+# Contributing to AStar Dev OneDrive Sync Client
+
+Thank you for your interest in contributing! This document provides guidelines for contributing to the project.
+
+---
+
+## Code Review Checklist
+
+Before submitting a pull request, ensure your code meets these requirements:
+
+### Code Quality
+- [ ] Code follows naming conventions and style guide ([style-guidelines](instructions/style-guidelines.instructions.md))
+- [ ] All public members have XML documentation comments
+- [ ] No warnings (project has `TreatWarningsAsErrors = true`)
+- [ ] Code is properly formatted (use IDE formatter)
+
+### Architecture & Design
+- [ ] New services/repositories have interfaces for testability
+- [ ] Business logic is abstracted behind interfaces (no `new` instantiation of services)
+- [ ] Dependencies injected via constructor parameters
+- [ ] Follows layered architecture (Core → Infrastructure → Presentation)
+
+### Testing
+- [ ] TDD workflow followed (failing test committed in branch history)
+- [ ] Tests cover happy path and error cases
+- [ ] Unit tests for business logic (80%+ coverage)
+- [ ] Integration tests for cross-service flows (where applicable)
+- [ ] All existing tests pass locally
+
+### Database Changes
+- [ ] Database changes have Entity Framework migrations
+- [ ] Migration reviewed and tested
+- [ ] Migration includes `Up()` and `Down()` methods for rollback
+
+### Async/Concurrency
+- [ ] Async/await used throughout (no `Task.Wait()` or `Task.Result`)
+- [ ] `CancellationToken` parameters added to async methods
+- [ ] Proper disposal of resources (`using` statements)
+
+### Documentation
+- [ ] README updated (if applicable)
+- [ ] API documentation added for public interfaces
+- [ ] Comments explain "why", not "what" (code should be self-explanatory)
+
+---
+
+## Commit Message Style
+
+
+Use conventional commits format for all commit messages. This enables automatic changelog generation and semantic versioning.
+
+
+### Format
+```
+():
+
+
+
+