Vellum

Short Intro: Vellum is a unified LLM development platform founded in January 2023 by Akash Sharma, Sidd Seethepalli, and Noa Flaherty, three engineers who built production LLM applications with GPT-3 at Dover starting in mid-2020, two years before ChatGPT. Coming out of Y Combinator's Winter 2023 batch and backed by $29.5M including a $20M Series A led by Leaders Fund in July 2025, Vellum gives engineering and product teams a shared environment to version prompts, orchestrate multi-step workflows, run evaluations, and monitor production LLM behavior without scattering that logic across application code.

Key Capabilities:

• Prompt editor with version control and GitHub-style release management

• Side-by-side model comparison across OpenAI, Anthropic, and other major providers

• Workflow builder for chaining multiple LLM calls, logic, and data sources

• Evaluation framework with quantitative metrics and custom scoring

• Out-of-the-box RAG without additional backend infrastructure

• Semantic search for injecting company-specific context into prompts

• Stable API interface decoupling prompts from application code

• Production monitoring and observability for deployed LLM workflows

• No-code LLM builder for non-technical team members

• Few-shot example management within the prompt editor

• Deployment and rollback with performance monitoring for edge case detection

• Python and TypeScript SDKs for programmatic integration

See Vellum Pricing Details →