# Implementation Plans
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This directory contains planning documents for major features that have been **implemented**.
These plans are kept for:
- Understanding the design rationale
- Reference for future similar work
- Historical context on implementation decisions
## Active Plans
| [jq.md](jq.md) | Implemented | `src/jq/` | jq query language for JSON |
| [dsv.md](dsv.md) | Implemented | `src/dsv/` | DSV (CSV/TSV) semi-indexing |
| [yq.md](yq.md) | Implemented | `src/yaml/`, `yq_runner.rs` | yq command for YAML |
| [yq-memory-optimization.md](yq-memory-optimization.md) | Partial | `yq_runner.rs`, `eval_generic.rs` | yq memory reduction plan |
| [compact-index-investigation.md](compact-index-investigation.md) | Proposed | `src/yaml/index.rs` | Elias-Fano for position arrays |
| [m2-benchmark-improvements.md](m2-benchmark-improvements.md) | Proposed | `yq_bench.rs` | Benchmark M2 streaming path |
| [simd-features.md](simd-features.md) | Current | `src/yaml/simd/` | YAML SIMD feature flag matrix |
## Plan Status Legend
- **Implemented**: Feature exists in codebase, plan reflects final design
- **Current**: Document describes current code behavior
- **Archived**: Plan superseded or approach changed
## Using Plans
When implementing similar features:
1. Review relevant plan for design patterns
2. Note any lessons learned sections
3. Check archive for rejected approaches
If the codebase diverges from a plan, the plan should be updated or archived.