
RAG Runtime Kernel: Applying event-sourced state machines and write-ahead logging to LLM orchestration -- a formal specification approach
Most LLM orchestration frameworks treat state management as an afterthought -- ad-hoc key-value stores, unvalidated context windows, no recovery guarantees. We took a different approach: what if we applied formal systems engineering to the problem?
RAG Runtime Kernel is an event-sourced, filesystem-backed state management system for LLMs, defined by a 43-section specification (v3.1.6).
Core architecture:
- Deterministic state machine with defined transitions: BOOTING -> READY -> WORKING -> CHECKPOINTING -> CLOSING. Every state has explicit entry/exit conditions.
- Proposal -> Validate -> Commit contract for all state mutations. The LLM proposes changes; the runtime validates against schema and transition rules; only valid proposals get committed. This is borrowed directly from database transaction theory.
- Event sourcing over CRUD. State is reconstructed from an append-only event log, giving you full audit trails and temporal queries.
- Write-ahead logging (WAL) with hash verification and atomic writes. Crash recovery is deterministic, not best-effort.
- HOT/COLD memory partitioning manages context window utilization -- active working state stays loaded, archival state gets paged in on demand.
The system is LLM-agnostic by design. It operates at the prompt/specification level, meaning it works with any model that can follow structured instructions -- local models, API providers, fine-tuned variants.
Two operational modes: AUTONOMOUS (specification-only, zero code) and ENFORCED (Python runtime with 8 modules, 337 passing tests, 5811 lines of hard validation).
The v3.2 Runtime Bridge provides the enforcement layer. Benchmarks against existing approaches (multi-tool IDE stacks, context management libraries) show competitive or superior results for structured state persistence.
MIT licensed: https://github.com/arcadamarket/rag-runtime-kernel
Interested in feedback from anyone working on formal methods for LLM systems or structured generation.