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CodingPaid Released July 2023

Vellum

LLM dev platform — prompt versioning, evals, monitoring in one tool.

Visit Vellum From $500/mo

Quick verdict

Best for
Teams shipping LLM features to production
Pricing
From $500/mo
Not ideal if
Pricey for early-stage startups

What is Vellum?

Vellum is the developer platform for building production LLM apps. Prompt management with versioning, A/B testing, evals against your own datasets, production monitoring. Used by teams shipping AI features at companies like Drata, Anrok, and Replicate.

Key features

  • Prompt versioning + A/B testing
  • Eval suites with your data
  • Multi-model routing
  • Production observability
  • Prompt collaboration (PMs + engineers)
  • API + SDK

Pros

  • Genuinely replaces 4-5 separate tools
  • Strong evals workflow
  • PMs can collaborate without code

Cons

  • Pricey for early-stage startups
  • Some overlap with LangSmith
  • Learning curve in week 1

Best for

Teams shipping LLM features to productionPMs working with engineers on promptsCompanies running A/B tests across modelsSeries A-C startups

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