Mastra

Mastra is an open-source TypeScript framework for building production-ready AI agents, agentic workflows, and RAG pipelines. Created by the team behind Gatsby (Sam Bhagwat CEO, Abhi Aiyer CTO, Shane Thomas CPO), it graduated from Y Combinator''s Winter 2025 batch with $13M in funding and reached v1.0 in January 2026. As of May 2026, the framework has 24.6k+ GitHub stars and 300k+ weekly npm downloads. Mastra fills a real gap in the agent ecosystem: while LangChain, CrewAI, and AutoGen began in Python with later JavaScript ports, Mastra was designed from the ground up for TypeScript: the language most web developers already know. The framework provides core primitives: agents (autonomous LLM-driven decision makers), tools (typed external integrations via Zod schemas), and workflows (deterministic multi-step pipelines), plus built-in memory systems, MCP server support, RAG with vector database management, supervisor patterns for multi-agent orchestration, evals, observability, and Mastra Studio (a visual IDE for testing and debugging). The model router connects to 3,300+ models from 94 providers (OpenAI, Anthropic, Google Gemini, DeepSeek, Groq, Mistral, xAI Grok, Amazon Bedrock, Azure OpenAI, Ollama, OpenRouter, Vercel, Hugging Face, Cohere, Cerebras, and more) through one standard interface with automatic fallbacks and IDE autocomplete. Production users include Replit (Mastra powers Replit''s agent builder), Factorial, Counsel Health, Cedar, and SoftBank. Pricing: the core framework is open source under Apache 2.0 and free for any use. Enterprise features (RBAC, SSO, ACL) reside in the ee/ directory and require a commercial license for production use but are freely usable for development and testing. Mastra Cloud is a hosted platform with GitHub-connected deployments, autoscaling, instant rollbacks, and centralized observability. Mastra Cloud pricing (as of May 2026): Starter is free at $0/month (100K observability events, 24 CPU hours, 15 days data retention). Teams is $250/month (1M events, 250 CPU hours, 6 months retention, multiple teams, SSO, SOC 2 docs). Enterprise is custom pricing (custom volume and retention, RBAC, audit logs, uptime SLAs, dedicated support engineer). Self-hosted deployment is available at no cost. Best fit: TypeScript and JavaScript developers building production AI agents without learning Python, full-stack web teams adding agentic features to Next.js, React, Express, or Hono apps, and platform companies (like Replit) embedding agent infrastructure into their own products. Who Mastra is not for: Python-only shops or teams committed to LangChain and CrewAI Python workflows cannot use Mastra without rewriting in TypeScript. Teams needing turn-key no-code agent builders rather than developer frameworks should consider Botpress, Voiceflow, or Microsoft Copilot Studio instead. Teams requiring enterprise compliance documentation (SOC 2, ISO 27001) are available on the Teams and Enterprise Mastra Cloud tiers.