ck (seek) finds code by meaning, not just keywords. It’s grep that understands what you’re looking for — search for “error handling” and find try/catch blocks, error returns, and exception handling code even when those exact words aren’t present.
This is free and open source software.
Features include:
- AI Agent Integration (MCP Server).
- Interactive TUI (Terminal User Interface):
- Multiple Search Modes: Toggle between Semantic, Regex, and Hybrid search with Tab
- Preview Modes: Switch between Heatmap, Syntax highlighting, and Chunk view with Ctrl+V
- View Options: Toggle between snippet and full-file view with Ctrl+F
- Multi-select: Select multiple files with Ctrl+Space, open all in editor with Enter
- Search History: Navigate with Ctrl+Up/Down
- Editor Integration: Opens files in $EDITOR with line numbers (Vim, VS Code, Cursor, etc.)
- Progress Tracking: Live indexing progress with file and chunk counts
- Config Persistence: Preferences saved to ~/.config/ck/tui.json
- Semantic Search – find code by concept, not keywords. Understands synonyms, related terms, and conceptual similarity.
- Drop-in grep compatibility.
- Hybrid search.
- Automatic Delta Indexing with Chunk-Level Caching:
- Semantic and hybrid searches transparently create and refresh their indexes before running. The first search builds what it needs; subsequent searches intelligently reuse cached embeddings:
- Chunk-level incremental indexing: Only changed chunks are re-embedded (80-90% cache hit rate for typical code changes)
- Content-aware invalidation: Doc comments and whitespace changes properly invalidate cache
- Model consistency: Prevents silent embedding corruption when switching models
- Semantic and hybrid searches transparently create and refresh their indexes before running. The first search builds what it needs; subsequent searches intelligently reuse cached embeddings:
- Smart caching: Hash-based invalidation using blake3(text + trivia) for reliable change detection
- Smart File Filtering – automatically excludes cache directories, build artifacts, and respects .gitignore and .ckignore files.
Website: github.com/BeaconBay/ck
Support:
Developer: Mike Renwick
License: MIT License or Apache License 2.0
ck is written in Rust. Learn Rust with our recommended free books and free tutorials.
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