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+# Getting Started with the Roadmap
+
+This guide helps you navigate the development roadmap for the Rust ODE library.
+
+## Roadmap Structure
+
+```
+roadmap/
+├── README.md                  # Master overview with all features
+├── GETTING_STARTED.md        # This file
+├── FEATURE_TEMPLATES.md      # Brief summaries of features 6-38
+└── features/
+    ├── 01-bs3-method.md      # Detailed implementation plan (example)
+    ├── 02-vern7-method.md    # Detailed implementation plan
+    ├── 03-rosenbrock23.md    # Detailed implementation plan
+    ├── 04-pid-controller.md  # Detailed implementation plan
+    ├── 05-discrete-callbacks.md  # Detailed implementation plan
+    ├── 06-callback-set.md    # Brief outline
+    └── 12-auto-switching.md  # Detailed implementation plan
+    └── ... (create detailed files as needed)
+```
+
+## How to Use This Roadmap
+
+### 1. Review the Master Plan
+
+Start with `README.md` to see:
+- All 38 planned features organized by tier
+- Dependencies between features
+- Current completion status
+- Overall progress tracking
+
+### 2. Choose Your Next Feature
+
+**Recommended Order for Beginners:**
+1. Start with Tier 1 features (essential)
+2. Follow dependency chains
+3. Mix difficulty levels (alternate hard and easy)
+
+**Suggested First 5 Features:**
+1. **BS3 Method** (feature #1) - Easy, builds confidence
+2. **PID Controller** (feature #4) - Easy, immediate value
+3. **Discrete Callbacks** (feature #5) - Easy, useful capability
+4. **Vern7** (feature #2) - Medium, important algorithm
+5. **Linear Solver Infrastructure** (feature #18) - Hard but foundational
+
+### 3. Read the Detailed Feature File
+
+Each detailed feature file contains:
+- **Overview**: Quick introduction
+- **Why It Matters**: Motivation
+- **Dependencies**: What you need first
+- **Implementation Approach**: Algorithm details
+- **Implementation Tasks**: Detailed checklist
+- **Testing Requirements**: How to verify it works
+- **References**: Where to learn more
+- **Complexity Estimate**: Time and difficulty
+- **Success Criteria**: Definition of done
+
+### 4. Implement the Feature
+
+Follow the detailed task checklist:
+- [ ] Read references and understand algorithm
+- [ ] Implement core algorithm
+- [ ] Write tests
+- [ ] Document
+- [ ] Benchmark
+- [ ] Check off tasks as you complete them
+
+### 5. Update the Roadmap
+
+When you complete a feature:
+1. Check the box in `README.md`
+2. Update completion statistics
+3. Note any lessons learned or deviations from plan
+
+## Current State (Baseline)
+
+Your library already has:
+- ✅ Dormand-Prince 4(5) with dense output
+- ✅ Tsit5 with dense output
+- ✅ PI Controller
+- ✅ Continuous callbacks with zero-crossing detection
+- ✅ Solution interpolation interface
+- ✅ Generic over compile-time array dimensions
+- ✅ Support for second-order ODE problems
+
+This is a solid foundation! The roadmap builds on this.
+
+## Recommended Development Path
+
+### Phase 1: Core Algorithm Diversity (Tier 1)
+*Goal: Give users algorithm choices*
+
+1. BS3 - Easy, quick win
+2. Vern7 - High accuracy option
+3. Build linear solver infrastructure
+4. Rosenbrock23 - First stiff solver
+5. PID Controller - Better adaptive stepping
+6. Discrete Callbacks - More event types
+
+**Milestone**: Can handle both non-stiff and stiff problems efficiently.
+
+### Phase 2: Robustness & Automation (Tier 2)
+*Goal: Make the library production-ready*
+
+7. Auto-switching/stiffness detection
+8. Automatic initial step size
+9. More Rosenbrock methods (Rodas4)
+10. BDF method
+11. CallbackSet and advanced callbacks
+12. Saveat functionality
+
+**Milestone**: Library can solve most problems automatically with minimal user input.
+
+### Phase 3: Specialization & Performance (Tier 3)
+*Goal: Optimize for specific problem classes*
+
+13. Low-storage RK for large systems
+14. Symplectic integrators for Hamiltonian systems
+15. SSP methods for hyperbolic PDEs
+16. Verner suite completion
+17. Advanced linear/nonlinear solvers
+18. Performance optimizations (FSAL, custom norms)
+
+**Milestone**: Best-in-class performance for specialized problem types.
+
+## Development Tips
+
+### Testing Strategy
+
+Every feature should have:
+1. **Convergence test**: Verify order of accuracy
+2. **Correctness test**: Compare to known solutions
+3. **Edge case tests**: Boundary conditions, error handling
+4. **Benchmark**: Performance measurement
+
+### Reference Material
+
+When implementing a feature:
+1. Read the Julia implementation for guidance
+2. Check original papers for algorithm details
+3. Verify tableau/coefficients from authoritative sources
+4. Test against reference solutions from DiffEqDevDocs
+
+### Common Pitfalls
+
+- **Don't skip testing**: Numerical bugs are subtle
+- **Verify tableau coefficients**: Transcription errors are common
+- **Check interpolation**: Easy to get wrong
+- **Test stiff problems**: If implementing stiff solvers
+- **Benchmark early**: Performance problems easier to fix early
+
+## Getting Help
+
+### Resources
+
+1. **Julia's OrdinaryDiffEq.jl**: Reference implementation
+   - Location: `/tmp/diffeq_copy/OrdinaryDiffEq.jl/`
+   - Well-tested, can compare behavior
+
+2. **Hairer & Wanner textbooks**:
+   - "Solving ODEs I: Nonstiff Problems"
+   - "Solving ODEs II: Stiff and DAE Problems"
+
+3. **DiffEqDevDocs**: Developer documentation
+   - https://docs.sciml.ai/DiffEqDevDocs/stable/
+
+4. **Test problems**: Standard ODE test suite
+   - Van der Pol, Robertson, Pleiades, etc.
+   - Reference solutions available
+
+### Creating New Detailed Feature Files
+
+When ready to work on a feature that only has a brief summary:
+
+1. Copy structure from `features/01-bs3-method.md`
+2. Fill in details from `FEATURE_TEMPLATES.md`
+3. Add algorithm-specific information
+4. Create comprehensive task checklist
+5. Define specific test requirements
+6. Estimate complexity honestly
+
+## Tracking Progress
+
+### In README.md
+
+Update the checkboxes as features are completed:
+- [ ] Incomplete
+- [x] Complete
+
+Update completion statistics at bottom:
+```
+## Progress Tracking
+
+Total Features: 38
+- Tier 1: 8 features (3/8 complete)  # Update these
+- Tier 2: 12 features (0/12 complete)
+- Tier 3: 18 features (0/18 complete)
+```
+
+### Optional: Keep a CHANGELOG.md
+
+Document major milestones:
+```markdown
+# Changelog
+
+## 2025-01-XX
+- Completed BS3 method
+- Completed PID controller
+- Started Vern7 implementation
+
+## 2025-01-YY
+- Completed Vern7
+- Linear solver infrastructure in progress
+```
+
+## Questions to Ask Before Starting
+
+Before implementing a feature:
+
+1. **Do I understand the algorithm?**
+   - Read the papers
+   - Understand the math
+   - Know the use cases
+
+2. **Are dependencies satisfied?**
+   - Check the dependency list
+   - Make sure infrastructure exists
+
+3. **Do I have test cases ready?**
+   - Know how to verify correctness
+   - Have reference solutions
+
+4. **What's the success criteria?**
+   - Clear definition of "done"
+   - Performance targets
+
+## Next Steps
+
+1. Read `README.md` to see the full roadmap
+2. Pick a feature to start with (suggest: BS3 or PID Controller)
+3. Read its detailed feature file
+4. Implement following the task checklist
+5. Test thoroughly
+6. Update the roadmap
+7. Move to next feature!
+
+Good luck! You're building something great. 🚀