# Spanlens: Free Open Source Alternative to Galileo, Humanloop, LangSmith

Canonical: https://caniforkit.com/fork/spanlens
Last updated: 2026-11-07

Spanlens (Open Source, Open Source) replaces Galileo, Humanloop, LangSmith, Maxim. Drop-in observability platform for OpenAI, Anthropic, and Gemini that logs every request, tracks costs, traces agent workflows, and flags anomalies and PII.

## Tool Specifications
- **Tool Name**: Spanlens
- **Type**: Open Source Project
- **License**: Open Source
- **Official Website**: https://www.spanlens.io/
- **GitHub Repository**: https://github.com/spanlens/Spanlens
- **GitHub Stars**: ★ 13
- **Runs On**: Self-host
- **Maintenance Status**: nov 2026
- **Platforms**: web, self-hosted, docker to self-host
- **Data Storage**: All application data and configuration live on your own server or local database.
- **Installation**: Clone https://github.com/spanlens/Spanlens or deploy with Docker Compose
- **Setup Requirements**: Deploy via Docker or binary release from GitHub and configure environment variables.
- **The Catch / Limitation**: Requires self-hosting setup, updates, and server maintenance compared to managed Galileo.

## Paid SaaS Applications Replaced (4)
Replacing these paid tools with Spanlens saves up to $140/mo ($1,680/yr) in software subscriptions:

| Replaced Software | Category | SaaS Price | Comparison Guide |
| --- | --- | --- | --- |
| [Galileo](https://caniforkit.com/galileo) | [analytics](https://caniforkit.com/category/analytics) | $35/mo | [Compare Galileo vs Spanlens](https://caniforkit.com/vs/galileo-vs-spanlens) |
| [Humanloop](https://caniforkit.com/humanloop) | [analytics](https://caniforkit.com/category/analytics) | $35/mo | [Compare Humanloop vs Spanlens](https://caniforkit.com/vs/humanloop-vs-spanlens) |
| [LangSmith](https://caniforkit.com/langsmith) | [analytics](https://caniforkit.com/category/analytics) | $35/mo | [Compare LangSmith vs Spanlens](https://caniforkit.com/vs/langsmith-vs-spanlens) |
| [Maxim](https://caniforkit.com/maxim) | [analytics](https://caniforkit.com/category/analytics) | $35/mo | [Compare Maxim vs Spanlens](https://caniforkit.com/vs/maxim-vs-spanlens) |

## Frequently Asked Questions

### Is Spanlens free and open source?
Spanlens is an open source tool licensed under Open Source that runs on self-host. Drop-in observability platform for OpenAI, Anthropic, and Gemini that logs every request, tracks costs, traces agent workflows, and flags anomalies and PII.

### What is the trade-off or limitation of using Spanlens?
Requires self-hosting setup, updates, and server maintenance compared to managed Galileo.

## Related

- [Self-Hosted Open Source Directory](https://caniforkit.com/self-hosted)
- [All Paid SaaS Alternatives Index](https://caniforkit.com/alternatives)
- [Software Categories Directory](https://caniforkit.com/categories)
- [Homepage](https://caniforkit.com)