diff --git a/AGENTS.md b/AGENTS.md
index 633a9b3..639c21f 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -22,3 +22,12 @@ Development workflow
 
 Note
 - This is a minimal, opinionated MVP to bootstrap cross-domain interoperability. It is not a full production system.
+
+What we're adding now (MVP roadmap refinements):
+- Core ontology extension: versioned ContractRegistry (contracts per name/version) for interop with adapters.
+- Bridge layer: a lightweight to_canonical / from_canonical mapping to connect domain LocalProblem data to the CatOpt canonical form.
+- Adapters: two starter adapters (rover, habitat) already present; bridge will enable canonical data exchange.
+- ADMM-lite core: keep the existing two-agent toy solver as a testbed; extend with delta-sync semantics conceptually in code comments and tests.
+- Governance / contracts: hook up a minimal conformance story via the contract registry + bridge; add a test to verify registry behavior.
+- MVP testing: unit tests for contract registry, end-to-end tests for bridge mapping (stubbed inputs/outputs) and existing admm_lite tests for solver stability.
+- Documentation: update README to reflect the MVP extension and how to run tests.
diff --git a/src/catopt_graph/bridge.py b/src/catopt_graph/bridge.py
new file mode 100644
index 0000000..fbc9473
--- /dev/null
+++ b/src/catopt_graph/bridge.py
@@ -0,0 +1,52 @@
+"""CatOpt-Graph Bridge: Canonicalization layer between domain adapters and CatOpt.
+
+This lightweight module provides mapping helpers to translate between
+domain-specific LocalProblem representations emitted by adapters and a
+canonical CatOpt representation used by the core solver/pipeline.
+"""
+from __future__ import annotations
+
+from typing import Any, Dict
+
+
+def to_canonical(local_problem: Dict[str, Any]) -> Dict[str, Any]:
+    """Map a domain LocalProblem into a canonical CatOpt representation.
+
+    This is intentionally small and opinionated to support MVP flows:
+    - Normalize keys
+    - Promote core fields (node, objective, constraints) into a stable shape
+    - Represent objective generically, e.g., quadratic/linear with coefficients
+    """
+    lp_type = local_problem.get("type") or "LocalProblem"
+    node = local_problem.get("node") or local_problem.get("id") or "unknown"
+    obj = local_problem.get("objective", {})
+
+    canonical: Dict[str, Any] = {
+        "type": "CanonicalLocalProblem",
+        "node": node,
+        "source_type": lp_type,
+        "objective": obj,
+        "metadata": {
+            "version": local_problem.get("version", "1.0.0"),
+        },
+    }
+    return canonical
+
+
+def from_canonical(canonical: Dict[str, Any]) -> Dict[str, Any]:
+    """Map a canonical CatOpt representation back to a domain-local form.
+
+    This function is intentionally minimal; in MVP it serves as a stub for
+    domain adapters to re-emit data in their native shapes.
+    """
+    if not isinstance(canonical, dict):
+        return {"error": "invalid canonical payload"}
+    # Pass through known fields if present
+    node = canonical.get("node", "unknown")
+    local_problem = {
+        "type": canonical.get("source_type", "LocalProblem"),
+        "node": node,
+        "objective": canonical.get("objective", {}),
+        "metadata": canonical.get("metadata", {}),
+    }
+    return local_problem
diff --git a/src/catopt_graph/core.py b/src/catopt_graph/core.py
index ac12110..a508f12 100644
--- a/src/catopt_graph/core.py
+++ b/src/catopt_graph/core.py
@@ -19,12 +19,45 @@ class Functor:
     map_to: str
 
 class ContractRegistry:
-    """Minimal versioned contract registry skeleton."""
+    """Minimal versioned contract registry skeleton.
+
+    This registry stores contracts (schemas, conformance rules, etc.) in a
+    versioned fashion for cross-domain adapters. Each contract name maps to a
+    dictionary of versions to contract payloads.
+    """
     def __init__(self) -> None:
+        # mapping: contract_name -> { version_str: contract_payload_dict }
         self.contracts: Dict[str, Dict[str, Any]] = {}
 
-    def register(self, name: str, contract: Dict[str, Any]) -> None:
-        self.contracts[name] = contract
+    def register_contract(self, name: str, contract: Dict[str, Any], version: str = "1.0.0") -> None:
+        """Register a contract with an explicit version (default 1.0.0).
 
-    def get(self, name: str) -> Optional[Dict[str, Any]]:
-        return self.contracts.get(name)
+        If the contract name does not exist, create a new versioned bucket.
+        If the version already exists, it will be overwritten to reflect the
+        new contract payload.
+        """
+        if name not in self.contracts:
+            self.contracts[name] = {}
+        self.contracts[name][version] = contract
+
+    def get_contract(self, name: str, version: str | None = None) -> Optional[Dict[str, Any]]:
+        """Return a contract payload by name and optional version.
+
+        If version is None, return the latest version available for the contract.
+        If the contract or version is not found, return None.
+        """
+        versions = self.contracts.get(name)
+        if not versions:
+            return None
+        if version is None:
+            # pick the latest version by semantic version string comparison
+            try:
+                latest = max(versions.keys(), key=lambda v: tuple(int(p) for p in v.split(".")))
+            except Exception:
+                latest = sorted(versions.keys())[-1]
+            return versions.get(latest)
+        return versions.get(version)
+
+    def list_contracts(self) -> Dict[str, Dict[str, Any]]:
+        """Return a raw view of all registered contracts."""
+        return self.contracts
diff --git a/tests/test_contract_registry.py b/tests/test_contract_registry.py
new file mode 100644
index 0000000..1d6e680
--- /dev/null
+++ b/tests/test_contract_registry.py
@@ -0,0 +1,33 @@
+import unittest
+
+from catopt_graph.core import ContractRegistry
+
+
+class TestContractRegistry(unittest.TestCase):
+    def test_register_and_get_contract_versions(self):
+        reg = ContractRegistry()
+        reg.register_contract("LocalProblem", {"foo": "bar"}, version="1.0.0")
+        reg.register_contract("LocalProblem", {"foo": "baz"}, version="1.1.0")
+
+        c_latest = reg.get_contract("LocalProblem")
+        c_10 = reg.get_contract("LocalProblem", version="1.0.0")
+        c_11 = reg.get_contract("LocalProblem", version="1.1.0")
+
+        self.assertIsNotNone(c_latest)
+        self.assertEqual(c_10, {"foo": "bar"})
+        self.assertEqual(c_11, {"foo": "baz"})
+
+        # The latest should reflect the highest version number
+        self.assertEqual(c_latest, c_11)
+
+    def test_list_contracts(self):
+        reg = ContractRegistry()
+        reg.register_contract("X", {"a": 1}, version="0.1.0")
+        reg.register_contract("Y", {"b": 2}, version="0.1.0")
+        all_contracts = reg.list_contracts()
+        self.assertIn("X", all_contracts)
+        self.assertIn("Y", all_contracts)
+
+
+if __name__ == "__main__":
+    unittest.main()