ck – semantic code search

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
• 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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