Federation Configuration

Federation

Federation connects multiple Synapses-indexed projects for cross-project queries. Essential for monorepos and microservice architectures.

{
  "federation": [
    {
      "path": "../shared-lib",
      "alias": "shared"
    },
    {
      "path": "../api-gateway",
      "alias": "gateway"
    }
  ]
}

Federation Entry Fields

Linked Projects

The linked field merges another project’s graph directly into this project’s graph:

{
  "linked": ["../shared-types"]
}

Linked projects are read-only — their nodes and edges appear in your graph but can’t be modified.

Federation ACL

Control what data sibling projects can read:

{
  "federation_acl": {
    "allow_reads": true,
    "allow_memory_reads": false,
    "allowed_projects": ["shared", "gateway"]
  }
}

Cross-Project Queries

Once configured, many tools support a projects parameter:

get_context(entity="ValidateToken", projects="shared,gateway")
get_impact(entity="AuthMiddleware", projects="*")
memory(action="search", query="auth changes", projects="shared")

How It Works

• Fail-open: Federation errors are logged, never propagated — your project works even if siblings are down
• Lazy loading: Sibling stores opened on first access, cached for session lifetime
• Stale threshold: Siblings not indexed in 24 hours are marked stale
• Parallelism: Up to 8 concurrent queries against siblings
• Timeout: 10 seconds per sibling query
• Drift detection: Automatically detects when cross-project dependencies change (signature changes, removals)