LangFast Description
LangFast is a streamlined prompt testing platform aimed at product teams, prompt engineers, and developers working with large language models. It offers immediate access to a customizable prompt playground without requiring signup, making prompt experimentation quick and hassle-free. Users can create, test, and share prompt templates using Jinja2 syntax, while receiving real-time raw outputs directly from the LLM, avoiding complicated API layers. This reduces the friction typically associated with manual prompt testing, allowing teams to validate and iterate faster. Developed by a team experienced in scaling AI SaaS products to millions of users, LangFast provides full control over the prompt development lifecycle. The platform also fosters improved team collaboration by enabling easy sharing and iteration. Its pay-as-you-go pricing ensures users only pay for what they use, keeping budgets under control. LangFast is ideal for teams seeking a flexible, cost-effective solution for prompt engineering.
LangFast Alternatives
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Google AI Studio
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PromptHub
Streamline your prompt testing, collaboration, versioning, and deployment all in one location with PromptHub. Eliminate the hassle of constant copy and pasting by leveraging variables for easier prompt creation. Bid farewell to cumbersome spreadsheets and effortlessly compare different outputs side-by-side while refining your prompts. Scale your testing with batch processing to effectively manage your datasets and prompts. Ensure the consistency of your prompts by testing across various models, variables, and parameters. Simultaneously stream two conversations and experiment with different models, system messages, or chat templates to find the best fit. You can commit prompts, create branches, and collaborate without any friction. Our system detects changes to prompts, allowing you to concentrate on analyzing outputs. Facilitate team reviews of changes, approve new versions, and keep everyone aligned. Additionally, keep track of requests, associated costs, and latency with ease. PromptHub provides a comprehensive solution for testing, versioning, and collaborating on prompts within your team, thanks to its GitHub-style versioning that simplifies the iterative process and centralizes your work. With the ability to manage everything in one place, your team can work more efficiently and effectively than ever before.
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Vellum AI
Introduce features powered by LLMs into production using tools designed for prompt engineering, semantic search, version control, quantitative testing, and performance tracking, all of which are compatible with the leading LLM providers. Expedite the process of developing a minimum viable product by testing various prompts, parameters, and different LLM providers to quickly find the optimal setup for your specific needs. Vellum serves as a fast, dependable proxy to LLM providers, enabling you to implement version-controlled modifications to your prompts without any coding requirements. Additionally, Vellum gathers model inputs, outputs, and user feedback, utilizing this information to create invaluable testing datasets that can be leveraged to assess future modifications before deployment. Furthermore, you can seamlessly integrate company-specific context into your prompts while avoiding the hassle of managing your own semantic search infrastructure, enhancing the relevance and precision of your interactions.
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Pricing
Pricing Starts At:
$60 one time
Free Trial:
Yes
Integrations
No Integrations at this time
Company Details
Company:
Langfa.st
Year Founded:
2025
Headquarters:
United States
Website:
langfa.st/new
Media
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Product Details
Platforms
Web-Based
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