# Benchkit Development Roadmap

- **Project:** benchkit
- **Version Target:** 1.0.0
- **Date:** 2025-08-08
- **Status:** ACTIVE

## Project Vision

Benchkit is a **toolkit, not a framework** for practical benchmarking with markdown-first reporting. It provides flexible building blocks that developers can combine to create custom benchmarking solutions tailored to their specific needs.

## Architecture Principles

- **Toolkit over Framework**: Provide composable functions rather than monolithic workflows
- **Markdown-First Reporting**: Treat markdown as first-class output format
- **Zero-Copy Where Possible**: Minimize allocations during measurement
- **Statistical Rigor**: Provide proper statistical analysis with confidence intervals

## Development Phases

### Phase 1: Core Functionality (MVP) - **Current Phase**

**Timeline:** Week 1-2  
**Justification:** Essential for any benchmarking work

#### Core Features
- [x] **Basic Timing & Measurement** (`enabled` feature)
  - Simple timing functions for arbitrary code blocks
  - Nested timing for hierarchical analysis
  - Statistical measures (mean, median, min, max, percentiles)
  - Custom metrics support beyond timing

- [x] **Markdown Report Generation** (`markdown_reports` feature)
  - Generate markdown tables and sections for benchmark results
  - Update specific sections of existing markdown files
  - Preserve non-benchmark content when updating documents

- [x] **Standard Data Generators** (`data_generators` feature)
  - Lists of varying sizes (small: 10, medium: 100, large: 1000, huge: 10000)
  - Maps with configurable key-value distributions
  - Strings with controlled length and character sets
  - Consistent seeding for reproducible benchmarks

#### Success Criteria
- [ ] New users can run first benchmark in <5 minutes
- [ ] Integration requires <10 lines of code
- [ ] Measurement overhead <1% for operations >1ms
- [ ] All core features work independently

#### Deliverables
1. **Project Structure**
   - Cargo.toml with proper feature flags
   - lib.rs with mod_interface pattern
   - Core modules: timing, generators, reports

2. **Core APIs**
   - `BenchmarkSuite` for organizing benchmarks
   - `bench_block` for timing arbitrary code
   - `MetricCollector` for extensible metrics
   - `generate_list_data`, `generate_map_data` generators

3. **Testing Infrastructure**
   - Comprehensive test suite in `tests/` directory
   - Test matrix covering all core functionality
   - Integration tests with real markdown files

### Phase 2: Analysis Tools

**Timeline:** Week 3-4  
**Justification:** Needed for optimization decision-making

#### Features
- [ ] **Comparative Analysis** (`comparative_analysis` feature)
  - Before/after performance comparisons
  - A/B testing capabilities for algorithm variants
  - Comparative reports highlighting differences

- [ ] **Statistical Analysis** (`statistical_analysis` feature)
  - Standard statistical measures for benchmark results
  - Outlier detection and confidence intervals
  - Multiple sampling strategies

- [ ] **Baseline Management**
  - Save and compare against performance baselines
  - Automatic regression detection
  - Percentage improvement/degradation calculations

#### Success Criteria
- [ ] Performance regressions detected within 1% accuracy
- [ ] Statistical confidence intervals provided
- [ ] Comparative reports show clear optimization guidance

### Phase 3: Advanced Features

**Timeline:** Week 5-6  
**Justification:** Nice-to-have for comprehensive analysis

#### Features
- [ ] **HTML Reports** (`html_reports` feature)
  - HTML report generation with customizable templates
  - Chart and visualization embedding
  - Interactive performance dashboards

- [ ] **JSON Reports** (`json_reports` feature)
  - Machine-readable JSON output format
  - API integration support
  - Custom data processing pipelines

- [ ] **Criterion Compatibility** (`criterion_compat` feature)
  - Compatibility layer with existing criterion benchmarks
  - Migration tools from criterion to benchkit
  - Hybrid usage patterns

- [ ] **Optimization Hints** (`optimization_hints` feature)
  - Analyze results to suggest optimization opportunities
  - Identify performance scaling characteristics
  - Actionable recommendations based on measurement patterns

#### Success Criteria
- [ ] Compatible with existing criterion benchmarks
- [ ] Multiple output formats work seamlessly
- [ ] Optimization hints provide actionable guidance

### Phase 4: Ecosystem Integration

**Timeline:** Week 7-8  
**Justification:** Long-term adoption and CI/CD integration

#### Features
- [ ] **CI/CD Tooling**
  - Automated performance monitoring in CI pipelines
  - Performance regression alerts
  - Integration with GitHub Actions, GitLab CI

- [ ] **IDE Integration**
  - Editor extensions for VS Code, IntelliJ
  - Inline performance annotations
  - Real-time benchmark execution

- [ ] **Monitoring & Alerting**
  - Long-term performance trend tracking
  - Performance degradation notifications
  - Historical performance analysis

## Technical Requirements

### Feature Flag Architecture

| Feature | Description | Default | Dependencies |
|---------|-------------|---------|--------------|
| `enabled` | Core benchmarking functionality | ✓ | - |
| `markdown_reports` | Markdown report generation | ✓ | pulldown-cmark |
| `data_generators` | Common data generation patterns | ✓ | rand |
| `criterion_compat` | Compatibility layer with criterion | ✓ | criterion |
| `html_reports` | HTML report generation | - | tera |
| `json_reports` | JSON report output | - | serde_json |
| `statistical_analysis` | Advanced statistical analysis | - | statistical |
| `comparative_analysis` | A/B testing and comparisons | - | - |
| `optimization_hints` | Performance optimization suggestions | - | statistical_analysis |

### Non-Functional Requirements

1. **Performance**
   - Measurement overhead <1% for operations >1ms
   - Data generation must not significantly impact timing
   - Report generation <10 seconds for typical suites

2. **Usability**
   - Integration requires <10 lines of code
   - Sensible defaults for common scenarios
   - Incremental adoption alongside existing tools

3. **Reliability**
   - Consistent results across runs (±5% variance)
   - Deterministic seeding for reproducible data
   - Statistical confidence measures for system noise

4. **Compatibility**
   - Primary: std environments
   - Secondary: no_std compatibility for core timing
   - Platforms: Linux, macOS, Windows

## Implementation Strategy

### Development Principles

1. **Test-Driven Development**
   - Write tests before implementation
   - Test matrix for comprehensive coverage
   - Integration tests with real use cases

2. **Incremental Implementation**
   - Complete one feature before starting next
   - Each feature must work independently
   - Regular verification against success criteria

3. **Documentation-Driven**
   - Update documentation with each feature
   - Real examples in all documentation
   - Performance characteristics documented

### Code Organization

```
benchkit/
├── Cargo.toml           # Feature flags and dependencies
├── src/
│   ├── lib.rs           # Public API and mod_interface
│   ├── timing/          # Core timing and measurement
│   ├── generators/      # Data generation utilities  
│   ├── reports/         # Output format generation
│   └── analysis/        # Statistical and comparative analysis
├── tests/               # All tests (no tests in src/)
│   ├── timing_tests.rs
│   ├── generators_tests.rs
│   ├── reports_tests.rs
│   └── integration_tests.rs
├── benchmarks/          # Internal performance benchmarks
└── examples/            # Usage demonstrations
```

## Integration Patterns

### Pattern 1: Inline Benchmarking
```rust
use benchkit::prelude::*;

fn benchmark_my_function() 
{
    let mut suite = BenchmarkSuite::new("my_function_performance");
    
    suite.benchmark("small_input", || {
        let data = generate_list_data(10);
        bench_block(|| my_function(&data))
    });
    
    suite.generate_markdown_report("performance.md", "## Performance Results");
}
```

### Pattern 2: Comparative Analysis
```rust
use benchkit::prelude::*;

fn compare_algorithms() 
{
    let comparison = ComparativeAnalysis::new()
        .algorithm("original", || original_algorithm(&data))
        .algorithm("optimized", || optimized_algorithm(&data))
        .with_data_sizes(&[10, 100, 1000, 10000]);
    
    let report = comparison.run_comparison();
    report.update_markdown_section("README.md", "## Algorithm Comparison");
}
```

## Risk Mitigation

### Technical Risks

1. **Measurement Accuracy**
   - Risk: System noise affecting benchmark reliability
   - Mitigation: Statistical analysis, multiple sampling, outlier detection

2. **Integration Complexity**
   - Risk: Difficult integration with existing projects
   - Mitigation: Simple APIs, comprehensive examples, incremental adoption

3. **Performance Overhead**
   - Risk: Benchmarking tools slowing down measurements
   - Mitigation: Zero-copy design, minimal allocations, performance testing

### Project Risks

1. **Feature Creep**
   - Risk: Adding too many features, losing focus
   - Mitigation: Strict phase-based development, clear success criteria

2. **User Adoption**
   - Risk: Users preferring existing tools (criterion)
   - Mitigation: Compatibility layer, clear value proposition, migration tools

## Success Metrics

### User Experience Metrics
- [ ] Time to first benchmark: <5 minutes
- [ ] Integration effort: <10 lines of code
- [ ] Documentation automation: Zero manual copying
- [ ] Regression detection accuracy: >99%

### Technical Metrics  
- [ ] Measurement overhead: <1%
- [ ] Feature independence: 100%
- [ ] Platform compatibility: Linux, macOS, Windows
- [ ] Memory efficiency: O(n) scaling with data size

## Next Actions

1. **Immediate (This Week)**
   - Set up project structure with Cargo.toml
   - Implement core timing module
   - Create basic data generators
   - Set up testing infrastructure

2. **Short-term (Next 2 Weeks)**
   - Complete Phase 1 MVP implementation
   - Comprehensive test coverage
   - Basic markdown report generation
   - Documentation and examples

3. **Medium-term (Month 2)**
   - Phase 2 analysis tools
   - Statistical rigor improvements
   - Comparative analysis features
   - Performance optimization

## References

- **spec.md** - Complete functional requirements and technical specifications
- **usage.md** - Lessons learned from unilang/strs_tools benchmarking
- **Design Rulebook** - Architectural principles and development procedures
- **Codestyle Rulebook** - Code formatting and structural patterns