spt-booster

Fast code editing library using tree-sitter and similarity matching

Overview

spt-booster automatically applies code edits by finding the best matching location in existing source code. It uses tree-sitter parsing (or a lightweight regex-based parser for WASM targets) combined with text similarity algorithms to locate where an edit should be applied. This is the Tier 1 "Agent Booster" in the SPT 3-tier model routing system, enabling sub-millisecond code transforms without invoking an LLM.

Key Features

• Tree-sitter parsing -- full AST-based code chunk extraction for JS/TS (optional feature)
• Lite parser fallback -- regex-based parser for WASM and constrained environments
• Template-based transforms -- fast path for common edits (var-to-const, add types) bypassing similarity matching
• Similarity matching -- finds best-fit code chunks using string distance algorithms
• Multi-language support -- JavaScript, TypeScript, Python, Rust, Go, Java, C, C++

Dependencies

Key internal dependencies:

• tree-sitter / tree-sitter-javascript / tree-sitter-typescript -- AST parsing (optional)
• strsim -- text similarity scoring
• regex -- lite parser fallback

Usage

use spt_booster::{SptBooster, Config, EditRequest, Language};

let config = Config::default();
let mut booster = SptBooster::new(config).unwrap();
let request = EditRequest {
    original_code: "let x = 1;".into(),
    edit_snippet: "const x = 1;".into(),
    language: Language::JavaScript,
    confidence_threshold: 0.8,
};
let result = booster.apply_edit(request).unwrap();

API Reference

Core Types

Type	Description
SptBooster	Main API for applying code edits
Config	Configuration for chunk limits and thresholds
EditRequest	Input describing the edit to apply
EditResult	Output with merged code and confidence score
CodeChunk	A parsed region of source code
Language	Supported programming language enum
MergeStrategy	How the edit was applied (ExactReplace, FuzzyReplace, etc.)
TemplateEngine	Fast-path template-based code transforms
SptBoosterError	Error type for parsing and merge failures