Kiln

The premium Open Source alternative to LangSmith

🎯 Best for:Teams looking to refine and evaluate LLM-based applications locally.

What is Kiln?

A comprehensive platform for building, evaluating, and optimizing AI systems through RAG, agents, and fine-tuning. It provides integrated tools for synthetic data generation and dataset management to improve LLM performance.

Tech Stack
PythonAI, ML & Data

Why Kiln?

  • End-to-end AI development lifecycle support
  • Strong focus on synthetic data generation
  • Open integration with various LLM providers

Limitations

  • Rapidly changing feature set
  • Requires significant compute for local evals
  • Documentation is developer-focused
3/5/2026
Last Update
346
Forks
46
Issues
Other
License
Financial Leak Detected

Stop the "SaaS Tax"

Your team could be burning cash. Switching to Kiln instantly boosts your runway.

Competitor Cost
-$1,440
/ year (est. based on LangSmith)
Self-Hosted
$0
/ year
Team Size10 Users
150+
SAVE 100%

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