About SubstrAI
SubstrAI is an open-source initiative producing enterprise-grade GenAI frameworks purpose-built for AWS Lambda and serverless infrastructure.
Existing LLM orchestration frameworks — LangChain, LlamaIndex, Semantic Kernel — assume long-running server processes with persistent memory, unlimited execution time, and heavy dependency trees. This makes them fundamentally incompatible with Lambda's stateless, cold-start-optimized, timeout-constrained execution model.
SubstrAI solves this by building each framework from first principles around serverless constraints: minimal package sizes (<5MB), DynamoDB-native state management, timeout-safe checkpoint/resume patterns, and cost-aware model routing.
Design Principles
- 1. Lambda-first — Purpose-built for serverless constraints (cold starts, 15-min timeout, stateless)
- 2. Convention over configuration — Works in 5 minutes with zero config
- 3. Observable by default — Every action traceable without extra setup
- 4. Cost-aware — Built-in budget enforcement and model routing
- 5. Escape hatches — Never trap the user; eject to raw CDK/SAM anytime