Graphiti is a Python library and server framework for building temporal knowledge graphs that serve as persistent memory for AI agents. It ingests unstructured text episodes (messages, transcripts, JSON), uses LLMs to extract entities and relationships with bi-temporal validity windows, deduplicates against existing graph data, and provides hybrid search (semantic + BM25 + graph traversal) with configurable reranking. The codebase is structured around a clean driver abstraction (Neo4j, FalkorDB, Kuzu, Neptune) with per-provider operations classes, a prompt library supporting versioning and overrides, and a multi-provider LLM/embedder/cross-encoder client system. It is primarily an application library, though it includes evaluation infrastructure and research-grade deduplication algorithms (MinHash/LSH).
BadWolf is a Go-based temporal graph store library and CLI tool designed for managing RDF-like triples with time-anchored predicates. It implements a custom query language (BQL) modeled after SPARQL, featuring a compiler pipeline architecture that includes lexical analysis, parsing, semantic analysis, and execution planning. The system supports immutable and temporal predicates, allowing queries to filter by time validity and perform temporal reasoning over graph data. It provides a pluggable storage abstraction layer, with a default in-memory implementation, and exposes functionality via a CLI tool (`bw`) and a simple HTTP server. The codebase demonstrates high craftsmanship in its query engine, utilizing a recursive descent parser with hook injection for semantic validation and a specificity-based planner for query optimization. The storage layer is decoupled via interfaces, enabling driver implementations to be swapped without modifying query logic. Extensive compliance testing ensures driver consistency across different backends. However, the project is explicitly pre-1.0, indicating API instability, and relies on a future Go version (1.24) in its module definition, suggesting experimental or forward-looking development practices. While primarily an application framework, it contains significant data engineering components, particularly in its temporal data modeling and query planning logic. The repository is suitable for engineers needing a temporal graph store or those looking to study compiler patterns applied to graph data. The CLI and server components provide immediate utility for testing and integration, while the library core offers reusable patterns for storage abstraction and query execution.