From 43ae6ef53f289768f1f89cae851db5ee2814eccc Mon Sep 17 00:00:00 2001
From: Marc-Antoine Parent <maparent@acm.org>
Date: Thu, 2 Jul 2026 09:21:55 -0400
Subject: [PATCH] eng-1863 Relation cross-app contract

---
 packages/database/src/crossAppContracts.ts | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/packages/database/src/crossAppContracts.ts b/packages/database/src/crossAppContracts.ts
index 63084917b..f64048453 100644
--- a/packages/database/src/crossAppContracts.ts
+++ b/packages/database/src/crossAppContracts.ts
@@ -25,6 +25,20 @@ export type CrossAppSchemaBase = CrossAppBase & {
   metadata?: Json;
 };
 
+type SpaceRef = DbRef | { url: string; sourceApp: Enums<"Platform"> };
+
+export type LocalOrRemoteRef =
+  | LocalRef
+  | {
+      localId: string;
+      // infer space from context if absent.
+      space?: SpaceRef;
+    }
+  | {
+      // A string that contains combined space and localId
+      rid: string;
+    };
+
 // A node schema
 export type CrossAppNodeSchema = CrossAppSchemaBase & {
   label: string;
@@ -76,3 +90,10 @@ export type CrossAppNode = CrossAppBase & {
     full: InlineCrossAppTypedContent;
   };
 };
+
+// A relation instance
+export type CrossAppRelation = CrossAppBase & {
+  relationType: Ref;
+  source: LocalOrRemoteRef;
+  destination: LocalOrRemoteRef;
+};