What is the main difference between Langfuse and Spanlens?

Langfuse and Spanlens are both llm observability & evaluation but differ in their approach, features, and target audience. Compare their GitHub stats, technology stack, and community adoption to make the best choice.

Which is better: Langfuse or Spanlens?

The choice between Langfuse and Spanlens depends on your specific needs, technical requirements, and team preferences. Both are quality open source solutions with active communities.

Can I migrate from Langfuse to Spanlens?

Migration between Langfuse and Spanlens is possible but requires careful planning. Consider data export/import capabilities, feature parity, and potential workflow changes.

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Langfuse vs Spanlens

Learn how Langfuse and Spanlens differ in their key features, development activity, technology stack and community adoption, so you can decide which of these llm observability & evaluation is best for you.

Langfuse

Langfuse provides tracing, evaluations, prompt management, and analytics to debug and improve LLM applications.

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37,139stars+1,565(+4.4%)

Last 30 days

Last commit
13 hours ago
Repository age
3 years
Version
v4.76.0
License
MIT
Self-hosted
Yes
Repository
langfuse/langfuse

Spanlens

Drop-in observability platform for OpenAI, Anthropic, and Gemini that logs every request, tracks costs, traces agent workflows, and flags anomalies and PII.

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13stars

Last 30 days

Last commit
2 days ago
Repository age
7 months
License
MIT
Self-hosted
Yes
Repository
spanlens/spanlens

Detailed Comparison

Langfuse appears to have several advantages over Spanlens, particularly in popularity and maturity. Consider your specific needs regarding popularity, activity, technology, maturity, licensing and features when making your decision.

Langfuse wins

Community & Popularity

Langfuse significantly outpaces Spanlens in community adoption with 37,139 stars compared to 13 stars on GitHub. This 2856.8x difference suggests Langfuse has a much larger and more active community. In terms of developer contributions, Langfuse has 4,171 forks, indicating strong developer engagement.

Comparable

Development Activity

Both projects show recent activity, with Langfuse last updated 13 hours ago and Spanlens 2 days ago.

Comparable

Technology Stack

Both tools share common technology foundations, being built with JavaScript, CSS, Bash, Typescript, JSX, Next.js. However, they differ in their additional technology choices: Spanlens leverages Python.

Langfuse wins

Project Maturity

Langfuse has been in development longer, starting 3 years ago, compared to Spanlens which began 7 months ago. This 3.0-year head start suggests Langfuse may have more mature features and established processes.

Comparable