semquery

Local-first search and answers for your documents.

semquery (short for semantic query) is a local, offline-ready RAG tool written in Rust. It indexes your personal document collections and lets you search or ask questions with cited answers — everything stays on your machine: indexes, models, and queries.

✨ What makes semquery different

• Offline document search & Q&A engine — Search passages or ask natural-language questions; everything runs locally with cited answers.
• Hybrid retrieval — Combines BM25 keyword search, dense vector search, RRF fusion, and cross-encoder reranking.
• Single-file index — Everything lives in one SQLite database (sqlite-vec + FTS5).
• Cited answers — ask returns natural-language answers with inline [N] citations pointing back to source files.
• Chinese-optimized — Sentence-level chunking and jieba word-level tokenization for BM25.
• Library-first workspace — Core traits live in semquery-core; heavy backends are isolated behind feature flags.

⚖️ Comparison with other tools

Feature	semquery	QMD	LlamaIndex	Chroma	Obsidian Smart Connections
Fully offline	✅	✅	⚠️ (cloud optional)	✅	❌ (uses OpenAI)
Single-file index	✅ SQLite	⚠️ SQLite (project-local optional)	❌	❌	❌
Hybrid retrieval (BM25 + vector + rerank)	✅	✅	✅ plugins	❌ vector only	❌
LLM query expansion	❌	✅	✅	❌	❌
MCP / agent integration	🚧 roadmap	✅	✅	❌	❌
Local LLM answers	✅	❌	✅	❌	⚠️
Chinese-optimized BM25	✅	⚠️	⚠️	❌	❌
Rust / native performance	✅	❌ Node/Bun	❌ Python	❌ Python	❌ JS
Rich output formats (JSON/CSV/XML/MD)	❌ JSON only	✅	✅	❌	❌
PDF / Office extraction	✅	❌	✅ plugins	❌	❌

🚀 Quick start

# Install from source
cargo install --path crates/semquery

# Create a workspace (uses ~/.config/semq by default)
semq init

# Add a directory of documents
semq add ~/notes --name notes

# Build the index
semq index

# Search for passages
semq search "quarterly revenue"

# Ask a question and get a cited answer
semq ask "What was the revenue in Q2?"

Run semq --help and semq <command> --help to discover all options.

📚 Supported document formats

• Markdown (.md) and plain text (.txt)
• PDF (.pdf) — enabled by default via the pdf feature
• Microsoft Word (.docx) — enabled by default via the docx feature

You can disable optional format support at build time with --no-default-features.

🧪 Try it with bundled test data

The repository includes sample documents under testdata/ (excerpts from the public tutorial Distributed System Illustrated by codedump.info). Try it without preparing your own files:

semq init
semq add testdata/ --name notes
semq index

# Search
semq search "Multi-Paxos improvements"

# Ask with citations
semq ask "What are the improvements of Multi-Paxos over the Paxos algorithm?"

# See step-by-step timing
 semq ask "What are the improvements of Multi-Paxos over the Paxos algorithm?" -v

It also works in Chinese:

semq ask "multi paxos 相比 paxos 算法的改进点？"

🏗️ Architecture

        cli (semq)
         │
         ▼
    semquery (Engine facade)
   ╱    │         ╲
retrieve  index   synthesize
  │       │          │
  ▼       ▼          ▼
storage + model backends
   ╲      │      ╱
        core

• semquery-core — Shared types, traits, and errors. Zero heavy dependencies.
• semquery-storage — SQLite implementation of the Storage trait (sqlite-vec, FTS5).
• semquery-indexer — File reading, chunking, and incremental indexing.
• semquery-retrieve — BM25 + vector recall → RRF → rerank.
• semquery-model — Local model backends: FastEmbed (embed/rerank) and llama.cpp (LLM).
• semquery-synth — Prompt building, LLM completion, and citation parsing.
• semquery — CLI and Engine facade.

🛠️ Global options

Every command accepts these flags:

• --workspace <path> — Use a different workspace directory.
• --config <path> / -c <path> — Use a custom configuration file.
• --model-cache <path> — Store downloaded models in a custom location.

Examples:

semq --workspace ./project-kb init
semq --workspace ./project-kb --config ./project-kb/semq.toml add ./docs --name docs
semq --workspace ./project-kb search "deployment checklist" --json

📤 Output formats

search, ask, and status support --json for machine-readable output:

semq search "budget approval" --json
semq ask "Who approved the budget?" --json
semq status --json

Use --explain with search to see the score breakdown:

semq search "budget approval" --explain

⚙️ Configuration

The global configuration file is created automatically on first run:

• macOS / Linux: ~/.config/semq/config.toml
• Windows: %LOCALAPPDATA%\semq\config.toml

Override it with --config.

📥 First-use downloads

The first time you index, search, or ask, semq downloads the required local models to --model-cache (~/.cache/semq/models by default). After that, everything works offline.

🎮 GPU acceleration

The prebuilt binary uses the CPU backend. On macOS (Apple Silicon), Metal GPU acceleration is enabled automatically during compilation. On Windows and Linux, build from source:

Vulkan (Windows / Linux — AMD, Intel, NVIDIA)

Install the Vulkan SDK, then:

cargo install semquery --features llama-cpp-2/vulkan

CUDA (Linux / Windows — NVIDIA only)

Install the CUDA Toolkit, then:

cargo install semquery --features llama-cpp-2/cuda

If no GPU is available at runtime, semq automatically falls back to CPU.

🗺️ Roadmap

• MCP server for agent integration
• LLM query expansion for hybrid retrieval
• xlsx / csv indexing
• File-watcher auto-indexing
• semq model subcommand for model management
• Customizable output formats (e.g. JSON, CSV, Markdown)
• Cited answers with source snippets and referenced content
• Prebuilt release binaries

🚧 Status

Early development. The CLI and configuration may change before 1.0. Issues and PRs are welcome.

📄 License

MIT OR Apache-2.0