Prism

Language feature coverage · details

Algorithm test coverage · details

Prism

Prism is a Code Property Graph (CPG) engine for diff-aware program slicing. It builds a unified graph — call graph, data flow graph, and control flow graph — from source code using tree-sitter and petgraph, then runs 30 slicing algorithms against diffs to extract exactly the context a code reviewer needs.

The problem: Raw diffs show what changed but not why it matters. A 5-line change to a validation function might affect 40 callers across 12 files. A new parameter might break a taint path from user input to a SQL query. Prism answers these questions statically and fast — typically under 3 seconds for a 50-file repository.

How it works:

1. Parse all source files into ASTs (tree-sitter — 11 languages, 12 grammar variants; TSX parsed separately from TypeScript)
2. Build a unified CPG: call graph + data flow graph + control flow graph
3. Enrich with type information (per-language providers, RTA for dispatch)
4. Accept a diff (unified patch or JSON)
5. Run selected algorithms against the diff, querying the CPG
6. Output focused slices: the exact code context relevant to each change

Use cases:

• Power automated code review agents with structured program analysis
• Pre-review triage: identify which changes are high-risk before human review
• Security analysis: trace taint paths from untrusted input to sensitive sinks
• Firmware/embedded review: detect missing resource cleanup, absent error handling
• Refactoring safety: verify that signature changes don't break callers

Implements 30 slicing algorithms spanning the paper Towards Practical Defect-Focused Automated Code Review, the established program slicing taxonomy, and several novel theoretical extensions including spiral, quantum, horizontal, vertical, angle, and 3D slices.

Supports Python, JavaScript, TypeScript, Go, Java, C, C++, Rust, Lua, Terraform/HCL, and Bash.

---

Install

Requires Rust 1.70+.

git clone <repo-url> && cd slicing
cargo build --release

The binary lands at target/release/slicing. Copy it somewhere on your $PATH or run it directly.

Note: The binary is named slicing for historical reasons. The project is called Prism. A rename is planned for a future release.

---

Quick start