# splice
[](https://crates.io/crates/splice)
[](https://docs.rs/splice)
**Version:** 2.6.1
Span-safe refactoring kernel for 7 languages. Byte-accurate code editing with graph algorithm analysis.
**Positioning:** Precision editing tool for codebases indexed by Magellan. Use for cross-file rename, impact analysis, and verified refactoring.
## Purpose
**splice edits code with graph-aware safety.** Built for:
- **Developers** — Cross-file rename, safe refactoring with rollback
- **Grounded Assistants** — Byte-accurate edits with proof-based verification
- **Tooling** — Scriptable transformations with AST validation
## Features
- **Span-safe editing** — Byte-accurate replacements with tree-sitter validation
- **Cross-file rename** — Symbol rename across entire codebase
- **Graph algorithms** — Reachability, dead-code, cycles, condense, slice
- **Impact analysis** — Blast zone detection before editing
- **Proof-based refactoring** — Machine-checkable behavioral equivalence
- **Code completion** — Grounded, import-aware suggestions using Magellan database
- Cross-file symbol resolution via import tracking
- Distinguishes local vs imported symbols with source tracking
- Token filtering and enhanced ranking for imported symbols
- Performance: low-millisecond internal query time on indexed project databases
- **7 languages** — Rust, Python, C, C++, Java, JavaScript, TypeScript
## Quick Start
```bash
# Install
cargo install splice
# Requires Magellan database (create first)
magellan watch --root ./src --db .magellan/splice.db
# Check status
splice status --db .magellan/splice.db
# Find reachable code from main
splice reachable --symbol main --path src/main.rs --db .magellan/splice.db
# Cross-file rename
splice rename --symbol old_name --to new_name --path src/lib.rs --db .magellan/splice.db
# Code completion (import-aware)
splice complete --file src/lib.rs --line 27 --column 8 --db .magellan/splice.db --max-results 10
```
## Installation
```bash
cargo install splice
```
## Backends
| (default) | SQLite backend | `.db` | Compatibility |
| `geometric` | Geometric analysis backend | `.geo` | Spatial/CFG analysis experiments |
## Requirements
- **[Magellan](https://github.com/oldnordic/magellan)** 3.1.7+ — Required for code graph
- **[sqlitegraph](https://crates.io/crates/sqlitegraph)** 2.0.3+ — Included automatically
## Documentation
- **[MANUAL.md](MANUAL.md)** — Complete command reference and examples
- **[CHANGELOG.md](CHANGELOG.md)** — Version history
- **[docs/completion.md](docs/completion.md)** — Code completion feature documentation
## What splice Does NOT Do
- ❌ Index code (use [Magellan](https://github.com/oldnordic/magellan))
- ❌ Search code (use [llmgrep](https://github.com/oldnordic/llmgrep))
- ❌ CFG analysis (use [Mirage](https://github.com/oldnordic/mirage))
- ❌ Type checking (use Compiler/LSP)
## License
GPL-3.0-or-later. See [LICENSE](LICENSE).