
Helicone AI
LangSmith
LangChain
Portkey
Braintrust.dev
PromptLayer
liteLLM
Langfuse is an open-source LLM engineering platform that helps teams collaboratively debug, analyze, and iterate on their LLM applications.

Auth0
Clerk
Keycloak
AuthKit
PropelAuth
Hanko
ZITADEL
Open-source Auth0/Clerk Alternative

Which is more popular?
Based on our record, Langfuse should be more popular than Stack Auth. It has been mentioned 36 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | langfuse.com | stack-auth.com |
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| Company | Startup from the United States | — |
| Listed in |
In their own words, as submitted to SaaSHub.


Langfuse is an open-source LLM engineering platform designed to empower developers by providing insights into user interactions with their LLM applications. We offer tools that help developers understand usage patterns, diagnose issues, and improve application performance based on real user data....
No description of Stack Auth yet.
What each product offers, as listed by its team.


Possible disadvantages
No features have been listed yet.
Walkthroughs and reviews on video.
Langfuse in two minutes
W18D3 C3: Full Stack Auth Review: User/Computer Order & Developer Build Order
How often each product is chosen within a category, 0–100% relative to the other.


Share your experience with using Langfuse and Stack Auth. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


Ten free AI prompt tools in 2026 across four categories: prompt generators (SurePrompts, Anthropic Console, OpenAI Playground), libraries (AIPRM, PromptHero, FlowGPT, Awesome ChatGPT Prompts), open-source workflow...
We have no reviews of Stack Auth yet. Be the first one to post
Recommendations tracked on public social media and blogs since March 2021.


Your agent gave a wrong answer, and every span in the trace is green. Both TraceRoot and Langfuse will show you that trace. This post compares what each one does next, from tracing and detection to a root cause and a fix. - Source: dev.to / 13 days ago
Langfuse is an open-source LLM engineering platform specialized for AI applications. It provides:. - Source: dev.to / about 1 month ago
Langfuse is an open-source observability and analytics platform for LLM applications. Its open-source nature is a significant draw for companies that prefer to self-host or want to avoid vendor lock-in. - Source: dev.to / about 2 months ago
Five minutes. That's how long Stack Auth takes to set up. - Source: dev.to / 12 months ago
Stack Auth (S24) | San Francisco, CA | Full-time Hiring founding & design engineers! We're building the customer platform for developers — think of a single service that does auth, payments, analytics, marketing emails, and so much more.... - Source: Hacker News / about 1 year ago
StackAuth is an open-source authentication and user management platform designed to integrate seamlessly into Next.js projects. Its combination of frontend/backend APIs and pre-built UI components dramatically simplifies the integration... - Source: dev.to / almost 2 years ago
When comparing Langfuse and Stack Auth, you can also consider the following products.

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Build and deploy LLM applications with confidence
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Clerk.io, the artificial intelligence for e-commerce that knows your customers interests.
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Framework for building applications with LLMs through composability
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Open Source Identity and Access Management for modern Applications and Services.
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