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RAG Frameworks · AnswerDotAI

byaldi

Byaldi is a Python library that wraps ColPali, a late-interaction multi-modal model, to enable retrieval-augmented generation (RAG) over documents and images. It provides a simple API for indexing PDFs and images, then searching them using visual understanding rather than text-only methods.

Source: GitHub — github.com/AnswerDotAI/byaldi
850
GitHub stars
92
Forks
Python
Primary language
Apache-2.0
License (OSI-approved)

Key facts

Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.

FieldValue
RepositoryAnswerDotAI/byaldi
OwnerAnswerDotAI
Primary languagePython
LicenseApache-2.0 — OSI-approved
Stars850
Forks92
Open issues44
Latest releasev0.0.5 (2024-10-03)
Last updated2025-01-28
Sourcehttps://github.com/AnswerDotAI/byaldi

What byaldi is

Byaldi wraps the colpali-engine to provide high-level APIs for multi-modal document indexing and retrieval. It converts PDFs to images, encodes them with ColVLM models (ColQwen2, ColPali), stores uncompressed indexes on disk, and returns scored results with optional base64 document payloads. Currently GPU-dependent for reasonable performance.

Quickstart

Get the byaldi source

Clone the repository and explore it locally.

terminalbash
git clone https://github.com/AnswerDotAI/byaldi.gitcd byaldi# follow the project's README for install & configuration

Need it deployed, integrated, or customized instead? DEV.co ships production installs.

Best use cases

Document retrieval with visual layout sensitivity

Ideal for RAG systems over documents where text extraction is unreliable or layout matters (forms, charts, multi-column layouts, diagrams). Avoids OCR brittleness.

Rapid prototyping of multi-modal search

Quick bootstrap for early-stage projects needing visual document understanding without building custom encoding pipelines. Minimal code to index and query.

Mixed media indexing

Supports both PDFs and image files in a single index, useful for knowledge bases containing screenshots, scans, diagrams, and structured documents.

Implementation considerations

  • GPU hardware is mandatory for usable throughput; encoding large document collections on CPU will be very slow.
  • System dependency on Poppler must be installed separately; Docker or CI/CD environments need explicit setup steps.
  • Index structure is uncompressed and in-memory; storage and RAM scale linearly with document count and model token count. Plan for large indices carefully.
  • Flash Attention is recommended but optional; installation may fail on older GPU architectures or CUDA versions.
  • Metadata and base64 encoding are optional but add significant storage overhead; choose `store_collection_with_index` carefully based on resource constraints.

When to avoid it — and what to weigh

  • Production scale with strict latency SLAs — Pre-release library using uncompressed indexes. No HNSW, quantization, or pooling yet. Encoding multi-billion-parameter models on CPU is impractical; GPU memory/cost may be prohibitive at scale.
  • Offline or CPU-only environments — Requires GPU for acceptable performance and multi-billion parameter model downloads. Poppler system dependency adds deployment overhead.
  • Text-centric retrieval over structured metadata — Optimized for visual/layout-aware search. Standard full-text search engines or sparse retrievers may be more efficient if documents are primarily text-based and queryable by keywords.
  • Minimal dependency footprint — Requires Poppler (system binary), Flash Attention (GPU optimization), pdf2image, and large transformer models. Not suitable for lightweight embedded scenarios.

License & commercial use

Apache License 2.0 (Apache-2.0). Permissive OSI license allowing commercial use, modification, and distribution with minimal restrictions (attribution and liability waiver required).

Apache-2.0 permits commercial use without royalties. However, verify compliance with licenses of underlying dependencies (ColPali, colpali-engine, pdf2image, Poppler). No commercial support, SLA, or official indemnification mentioned in the repository. Recommended to conduct full license audit for production deployments.

DEV.co evaluation signals

Editorial assessment — not user reviews. Directional, with an explicit confidence level.

SignalAssessment
MaintenanceActive
DocumentationAdequate
License clarityClear
Deployment complexityModerate
DEV.co fitGood
Assessment confidenceHigh
Security considerations

No explicit security audit or threat model disclosed. Pre-release software carries inherent risk. Poppler is a system binary with historical vulnerabilities; keep it patched. Indexes stored on disk are not encrypted. Model checkpoints are downloaded from Hugging Face Hub; ensure supply chain trust. No authentication or authorization mechanisms in the library itself.

Alternatives to consider

RAGatouille (parent project)

Earlier, more mature dense retrieval library from the same team. Use if ColBERT (sparse/dense hybrid) suffices and you do not need multi-modal support.

LlamaIndex with multi-modal integrations

Larger ecosystem with more backend options (Pinecone, Weaviate, Milvus), official support, and production-grade stability. Steeper learning curve but more extensible.

Vespa or Milvus with custom VLM encoders

Distributed vector databases with HNSW, quantization, and scaling built-in. Requires custom integration but better for large-scale deployments.

Software development agency

Build on byaldi with DEV.co software developers

Byaldi makes it simple to index and search documents using visual understanding. Ideal for rapid prototyping and early-stage RAG systems. Contact us to discuss architecture, GPU requirements, and production readiness for your use case.

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byaldi FAQ

Can I use Byaldi in production today?
Technically yes, but with caution. It is pre-release software with uncompressed indexes and acknowledged quirks. Suitable for MVP and early adoption; not recommended for mission-critical SLAs without thorough testing and resource planning.
What models are supported?
All models supported by colpali-engine, including ColQwen2 (vidore/colqwen2-v1.0) and original ColPali. Roadmap includes VisRAG and other ColVLM models. Check the colpali-engine repository for the current list.
Does Byaldi work on CPU?
Technically yes, but performance will be unacceptable for any real workload. Multi-billion parameter models are GPU-optimized. CPU inference is extremely slow; GPU is mandatory for practical use.
How do I scale Byaldi to many documents?
Current version uses uncompressed, in-memory indexes. For large-scale indexing, optimize by not storing base64 with the index, use a powerful GPU, and consider waiting for planned HNSW and quantization features. Distributed scenarios require custom orchestration.

Custom software development services

From first prototype to production, DEV.co delivers software development services around tools like byaldi. Our software development agency staffs experienced software developers and web developers for custom software development, web development, integrations, and ongoing support across rag frameworks and beyond.

Ready to explore multi-modal retrieval?

Byaldi makes it simple to index and search documents using visual understanding. Ideal for rapid prototyping and early-stage RAG systems. Contact us to discuss architecture, GPU requirements, and production readiness for your use case.