BackLens

BackLens helps you understand backend codebases as an interactive call graph directly inside VS Code.

It analyzes your project locally, builds a graph, and lets you inspect callers/callees, hotspots, and dependencies, then jump back to source in one click.

Why BackLens

BackLens is built for engineers who need to quickly answer architecture questions in unfamiliar code:

• What calls this method?
• Where does this class fan out?
• Which nodes are hottest in this project?
• How do I navigate from architecture view back to code?

Instead of tracing call flows manually across many files, you can explore them visually and navigate instantly.

Features

• Auto project detection
• One-click folder analysis from Explorer
• Interactive graph view with search and node inspection
• Caller/callee expansion for call flow exploration
• Hotspot and class/method exploration
• Double Click Go-to-source code navigation from graph nodes
• Re-analysis, refresh, and close project actions from the BackLens view

Demo / Screenshots

Current UI snapshots:

Hotspots and Method Expansion

Class Hierarchy and Inspector

Framework Call Graph View

Go-to-Source Navigation

Commands

• BackLens: Analyze Folder (backlens.analyzeFolder)
• BackLens: Re-analyze Folder (backlens.reanalyzeFolder)
• BackLens: Show Graph (backlens.showGraph)
• BackLens: Refresh (backlens.refreshExplorer)
• BackLens: Close Project (backlens.closeProject)
• BackLens: Go to Source (backlens.goToNode)

Quick Start

1. Open a workspace folder in VS Code.
2. Right-click your target folder in Explorer and run BackLens: Analyze Folder.
3. Run BackLens: Show Graph (or click View Graph after analysis).
4. Search, inspect callers/callees, and use BackLens: Go to Source to jump to code.

Requirements

• VS Code ^1.108.1
• A local folder/workspace containing source code

Supported Scope

Current strongest support:

• JavaScript
• TypeScript
• JSX/TSX parsing support

Current focus:

• Backend-oriented JS/TS repositories

BackLens does not currently claim first-class analysis support for Python, Go, or Rust.

Usage

1. Analyze a folder with BackLens: Analyze Folder.
2. Open the graph with BackLens: Show Graph.
3. Explore nodes with search, hotspot views, and caller/callee expansion.
4. Jump to implementation using BackLens: Go to Source.
5. Use the BackLens activity view to re-analyze, refresh, or close a project.

Local-First Privacy

BackLens runs analysis locally in your environment and stores graph data locally.

• No cloud account is required.
• No external service is required for extension mode.

Extension Settings

This extension currently does not contribute custom settings via contributes.configuration.

Known Limitations

• Static analysis has expected limits around dynamic runtime behavior.
• Framework-specific runtime magic may appear as unresolved or external.
• Current language support is strongest for JS/TS ecosystems.

Known Issues

• Test coverage is still minimal and focused on scaffold-level extension tests.

Release Notes

See CHANGELOG.md for release history.

Contributing

Contributions are welcome.

• Repository: github.com/adeebkhans/backlens

License

BackLens is open source under AGPL-3.0-only.

• Full license text: ../LICENSE
• Project notices: ../NOTICE
• Trademark policy: ../TRADEMARK.md