Know exactly what your changes break — before they do.
Impact Lens scans your entire codebase at symbol level, reads your git diff, and traces the blast radius of every change through a live dependency graph. Works in VS Code and Cursor.
Features
- Deep indexing — TypeScript, JavaScript, Python, Go, Ruby, Java, Rust, PHP, C/C++ supported
- Instant impact analysis — diff your working tree or any commit range and see affected files/symbols in seconds
- Visual blast-radius graph — interactive Cytoscape.js graph coloured by hop distance from the change
- AI summary — optional Claude or GPT-4 integration gives a plain-English risk assessment, suggested tests, and hotspot callouts
- Persistent index — SQLite-backed cache survives restarts; large repos load in under a second
Getting started
- Open a workspace and wait for "Index complete" in the Overview panel
- Click Analyze Impact (or
Cmd+Shift+P→ "Impact Lens: Analyze Impact") - Choose Working tree changes or Commit range
- The blast-radius graph and AI summary appear instantly
AI setup (optional)
Cmd+Shift+P → "Impact Lens: Configure AI Provider" → pick Claude or GPT-4 → enter your API key. Keys are stored in VS Code SecretStorage and never written to disk.
Settings
| Setting | Default | Description |
|---|---|---|
impactLens.aiProvider |
none |
claude, openai, or none |
impactLens.maxTraversalDepth |
10 |
Max BFS hops |
impactLens.excludePatterns |
see defaults | Glob patterns to skip |