Path (a) full-stack omni-emission visceral demo: write dsl/demos/todo_service.dag (TODO Item/List/User + mutations) → exercise the existing 4 emitters (Rust backend, SQL DDL, OpenAPI yaml, Markdown docs per src/v3/compiler/src/omni_shape_b_openapi.rs gates #25-#28 CONSUMER_LANDED+PASSING) → emit 4 a

dsl/demos/todo_service.dag

@@ -0,0 +1,167 @@
+// demos/todo_service — minimal TODO domain + REST operation table for omni-emission demos.
+//
+// Exercises Shape B projections in `omni_shape_b_openapi.rs` (OpenAPI 3.1 YAML,
+// Markdown drift-lock, SQL DDL route schema, runnable Rust backend) plus Shape A
+// `emit_rust` on one shared `compile_to_dag` result (r3-program-plan §1.8 #25–#28).
+//
+// Domain carriers are illustrated with small `data` inhabitants (human-facing
+// demo context). Omni route extraction still keys only on
+// `List<{ endpoint: RestEndpointBinding }>` rows (`v3.std.services`).
+
+module demos.todo_service
+
+import std.types { GET, POST, PUT, PATCH, DELETE, Int, String, Bool }
+import std.effects { LiteralToken, ParamToken }
+import v3.std.services { RestEndpointBinding }
+
+// Trivial root `let` so the module is not purely type-level (same cadence as
+// `omni_emit_anchor` in `m1_5_omni_shape_b_openapi_test` inline fixtures). Unused by route
+// extractors; keeps demo symmetry with other omni Shape B receipts.
+let todo_service_emit_anchor: Int = 0
+
+type User {
+  id:           String
+  display_name: String
+}
+
+type TodoItem {
+  id:          String
+  list_id:     String
+  title:       String
+  completed:   Bool
+}
+
+type TodoList {
+  id:          String
+  owner_id:    String
+  title:       String
+}
+
+type TodoServiceOperation {
+  endpoint: RestEndpointBinding
+}
+
+data todo_domain_example_user: User = {
+  id:           "demo-user",
+  display_name: "Demo User"
+}
+
+data todo_domain_example_item: TodoItem = {
+  id:        "demo-todo",
+  list_id:   "demo-list",
+  title:     "Wire domain carriers to example rows",
+  completed: false
+}
+
+data todo_domain_example_list: TodoList = {
+  id:       "demo-list",
+  owner_id: "demo-user",
+  title:    "Demo backlog"
+}
+
+data todo_service_operations: List<TodoServiceOperation> = [
+  {
+    endpoint: {
+      method: GET,
+      path: { tokens: [LiteralToken { text: "users" }] }
+    }
+  },
+  {
+    endpoint: {
+      method: POST,
+      path: { tokens: [LiteralToken { text: "users" }] }
+    }
+  },
+  {
+    endpoint: {
+      method: GET,
+      path: {
+        tokens: [LiteralToken { text: "users/" }, ParamToken { name: "userId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: PUT,
+      path: {
+        tokens: [LiteralToken { text: "users/" }, ParamToken { name: "userId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: DELETE,
+      path: {
+        tokens: [LiteralToken { text: "users/" }, ParamToken { name: "userId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: GET,
+      path: {
+        tokens: [
+          LiteralToken { text: "users/" },
+          ParamToken { name: "userId" },
+          LiteralToken { text: "/todos" }
+        ]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: POST,
+      path: {
+        tokens: [
+          LiteralToken { text: "users/" },
+          ParamToken { name: "userId" },
+          LiteralToken { text: "/todos" }
+        ]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: GET,
+      path: {
+        tokens: [LiteralToken { text: "todos/" }, ParamToken { name: "todoId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: PATCH,
+      path: {
+        tokens: [LiteralToken { text: "todos/" }, ParamToken { name: "todoId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: DELETE,
+      path: {
+        tokens: [LiteralToken { text: "todos/" }, ParamToken { name: "todoId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: GET,
+      path: {
+        tokens: [LiteralToken { text: "lists/" }, ParamToken { name: "listId" }]
+      }
+    }
+  },
+  {
+    endpoint: {
+      method: POST,
+      path: {
+        tokens: [
+          LiteralToken { text: "lists/" },
+          ParamToken { name: "listId" },
+          LiteralToken { text: "/todos" }
+        ]
+      }
+    }
+  }
+]

src/v3/compiler/tests/integration/m1_5_omni_shape_b_openapi_test.rs

@@ -129,6 +129,9 @@ import std.types { Int }
 let omni_emit_anchor: Int = 0
 "#;
 
+const TODO_SERVICE_REPOSITORY_SOURCE: &str =
+    include_str!("../../../../../dsl/demos/todo_service.dag");
+
 fn compile_omni_service_fixture() -> v3_compiler::Dag {
     std::thread::Builder::new()
         .name("m1_5_openapi_fixture_compile".to_string())
@@ -161,6 +164,89 @@ fn compile_empty_omni_service_fixture() -> v3_compiler::Dag {
         .expect("larger-stack compile thread completes")
 }
 
+fn compile_todo_service_repository_fixture() -> v3_compiler::Dag {
+    std::thread::Builder::new()
+        .name("m1_5_todo_service_repository_compile".to_string())
+        .stack_size(32 * 1024 * 1024)
+        .spawn(|| {
+            compile_to_dag(TODO_SERVICE_REPOSITORY_SOURCE, "dsl/demos/todo_service.dag")
+                .expect("repository todo_service.dag demo compiles")
+        })
+        .expect("spawn larger-stack compile thread")
+        .join()
+        .expect("larger-stack compile thread completes")
+}
+
+fn compile_todo_service_repository_fixture_counted(count: &mut usize) -> v3_compiler::Dag {
+    *count += 1;
+    compile_todo_service_repository_fixture()
+}
+
+fn expected_todo_service_routes() -> BTreeSet<RestRoute> {
+    BTreeSet::from([
+        RestRoute {
+            method: "DELETE".to_string(),
+            path: "/todos/{todoId}".to_string(),
+            path_parameters: vec!["todoId".to_string()],
+        },
+        RestRoute {
+            method: "DELETE".to_string(),
+            path: "/users/{userId}".to_string(),
+            path_parameters: vec!["userId".to_string()],
+        },
+        RestRoute {
+            method: "GET".to_string(),
+            path: "/lists/{listId}".to_string(),
+            path_parameters: vec!["listId".to_string()],
+        },
+        RestRoute {
+            method: "GET".to_string(),
+            path: "/todos/{todoId}".to_string(),
+            path_parameters: vec!["todoId".to_string()],
+        },
+        RestRoute {
+            method: "GET".to_string(),
+            path: "/users".to_string(),
+            path_parameters: vec![],
+        },
+        RestRoute {
+            method: "GET".to_string(),
+            path: "/users/{userId}".to_string(),
+            path_parameters: vec!["userId".to_string()],
+        },
+        RestRoute {
+            method: "GET".to_string(),
+            path: "/users/{userId}/todos".to_string(),
+            path_parameters: vec!["userId".to_string()],
+        },
+        RestRoute {
+            method: "PATCH".to_string(),
+            path: "/todos/{todoId}".to_string(),
+            path_parameters: vec!["todoId".to_string()],
+        },
+        RestRoute {
+            method: "POST".to_string(),
+            path: "/lists/{listId}/todos".to_string(),
+            path_parameters: vec!["listId".to_string()],
+        },
+        RestRoute {
+            method: "POST".to_string(),
+            path: "/users".to_string(),
+            path_parameters: vec![],
+        },
+        RestRoute {
+            method: "POST".to_string(),
+            path: "/users/{userId}/todos".to_string(),
+            path_parameters: vec!["userId".to_string()],
+        },
+        RestRoute {
+            method: "PUT".to_string(),
+            path: "/users/{userId}".to_string(),
+            path_parameters: vec!["userId".to_string()],
+        },
+    ])
+}
+
 fn expected_routes() -> BTreeSet<RestRoute> {
     BTreeSet::from([
         RestRoute {
@@ -700,3 +786,70 @@ fn openapi_projection_ignores_same_shape_non_service_endpoint_binding() {
          an OpenAPI route unless its field type is the canonical RestEndpointBinding."
     );
 }
+
+/// Repository `dsl/demos/todo_service.dag` visceral demo: one `compile_to_dag` feeds the
+/// four Shape B projections (OpenAPI YAML, Markdown, SQL DDL, Rust backend) plus Shape A
+/// `emit_rust`, matching r3-program-plan §1.8 #25–#28 structural discipline.
+#[test]
+fn todo_service_repository_demo_omni_layers_share_one_node_tree() {
+    // `compile_count` mirrors `omni_layers_share_one_node_tree`: one shared `Dag` is already
+    // enforced structurally because every projection takes `&dag`. The counter still ratchets
+    // accidental double acquisition via `compile_*_counted` (e.g. a duplicated helper call
+    // during edits), matching the §1.8 #28 receipt style in this module.
+    let mut compile_count = 0usize;
+    let dag = compile_todo_service_repository_fixture_counted(&mut compile_count);
+
+    let canonical = extract_rest_routes(&dag).expect("canonical route projection extracts");
+    assert_eq!(canonical, expected_todo_service_routes());
+
+    let openapi = project_openapi_yaml(&dag).expect("Shape B OpenAPI projects from shared DAG");
+    assert!(openapi.starts_with("openapi: 3.1.0\n"));
+    assert_eq!(openapi_yaml_routes(&openapi), canonical);
+
+    let markdown = project_markdown_documentation(&dag).expect("Markdown projects from shared DAG");
+    assert_eq!(markdown_documentation_routes(&markdown), canonical);
+
+    let ddl = project_sql_ddl_schema(&dag).expect("SQL DDL projects from shared DAG");
+    let ddl_routes = sql_ddl_routes(&ddl);
+    let canonical_without_parameters: BTreeSet<_> = canonical
+        .iter()
+        .map(|route| RestRoute {
+            method: route.method.clone(),
+            path: route.path.clone(),
+            path_parameters: vec![],
+        })
+        .collect();
+    assert_eq!(ddl_routes, canonical_without_parameters);
+    assert!(ddl.contains("  CHECK (method IN ("));
+    assert!(ddl.contains("'DELETE'"));
+    assert!(ddl.contains("'PATCH'"));
+    assert!(ddl.contains("'PUT'"));
+
+    let backend_source =
+        project_rust_backend_service(&dag).expect("backend service projects from shared DAG");
+    let (_tmp_dir, backend_bin) = compile_backend_service(&backend_source);
+    for route in &canonical {
+        let concrete_path = route
+            .path
+            .replace("{userId}", "42")
+            .replace("{todoId}", "99")
+            .replace("{listId}", "7");
+        assert_eq!(
+            backend_probe(&backend_bin, &route.method, &concrete_path),
+            "200",
+            "generated backend accepts route {} {}",
+            route.method,
+            concrete_path
+        );
+    }
+    assert_eq!(backend_probe(&backend_bin, "GET", "/missing"), "404");
+    assert_eq!(backend_probe(&backend_bin, "DELETE", "/users"), "404");
+    assert_eq!(backend_probe(&backend_bin, "GET", "/users/"), "404");
+
+    let _rust = emit_rust(&dag).expect("Shape A Rust emit consumes shared DAG");
+
+    assert_eq!(
+        compile_count, 1,
+        "Shape A + Shape B layers must consume the same compile_to_dag result for the repository demo"
+    );
+}