Configuration

Config section: graph:
Env prefix: LEX_GRAPH__

GraphConfig (Top Level)

Key	Type	Default	Env Variable	Description
enabled	bool	true	LEX_GRAPH__ENABLED	Enable graph store subsystem
backend	str	"memory"	LEX_GRAPH__BACKEND	Graph backend (memory or neo4j)
default_traversal_max_depth	int	10	LEX_GRAPH__DEFAULT_TRAVERSAL_MAX_DEPTH	Default traversal max depth
default_query_limit	int	100	LEX_GRAPH__DEFAULT_QUERY_LIMIT	Default query result limit
bulk_batch_size	int	1000	LEX_GRAPH__BULK_BATCH_SIZE	Batch size for bulk operations
max_retries	int	3	LEX_GRAPH__MAX_RETRIES	Max retries for operations
retry_delay	float	1.0	LEX_GRAPH__RETRY_DELAY	Delay between retries (seconds)
neo4j	Neo4jConfig	defaults	LEX_GRAPH__NEO4J__*	Neo4j-specific settings
memory	MemoryConfig	defaults	LEX_GRAPH__MEMORY__*	In-memory specific settings

Neo4jConfig

Key	Type	Default	Env Variable	Description
uri	str	"bolt://localhost:7687"	LEX_GRAPH__NEO4J__URI	Neo4j BOLT URI
username	str	"neo4j"	LEX_GRAPH__NEO4J__USERNAME	Neo4j username
password	SecretStr	""	LEX_GRAPH__NEO4J__PASSWORD	Neo4j password
database	str	"neo4j"	LEX_GRAPH__NEO4J__DATABASE	Target database name
max_connection_pool_size	int	100	LEX_GRAPH__NEO4J__MAX_CONNECTION_POOL_SIZE	Max connection pool size
connection_timeout	float	30.0	LEX_GRAPH__NEO4J__CONNECTION_TIMEOUT	Connection timeout (seconds)
max_transaction_retry_time	float	30.0	LEX_GRAPH__NEO4J__MAX_TRANSACTION_RETRY_TIME	Max transaction retry time
fetch_size	int	100	LEX_GRAPH__NEO4J__FETCH_SIZE	Default fetch size
encrypted	bool	false	LEX_GRAPH__NEO4J__ENCRYPTED	Use SSL/TLS encryption
trust	str	"TRUST_SYSTEM_CA_SIGNED_CERTIFICATES"	LEX_GRAPH__NEO4J__TRUST	Trust strategy for SSL

MemoryConfig

Key	Type	Default	Env Variable	Description
max_nodes	int	1000000	LEX_GRAPH__MEMORY__MAX_NODES	Maximum nodes in memory
max_edges	int	5000000	LEX_GRAPH__MEMORY__MAX_EDGES	Maximum edges in memory

---

Minimal YAML Example (In-Memory)

graph:
  backend: memory

Production YAML Example (Neo4j)

graph:
  backend: neo4j
  neo4j:
    uri: bolt://neo4j.example.com:7687
    username: neo4j
    password: ${NEO4J_PASSWORD}
    database: myapp
    max_connection_pool_size: 50
    encrypted: true

Environment Variable Override

export LEX_GRAPH__BACKEND="neo4j"
export LEX_GRAPH__NEO4J__URI="bolt://neo4j-cluster:7687"
export LEX_GRAPH__NEO4J__PASSWORD="s3cret!"
export LEX_GRAPH__DEFAULT_TRAVERSAL_MAX_DEPTH=5