diff --git a/packages/@orbit/data/src/query.ts b/packages/@orbit/data/src/query.ts
index e1b050abd..3daa47fd3 100644
--- a/packages/@orbit/data/src/query.ts
+++ b/packages/@orbit/data/src/query.ts
@@ -5,10 +5,14 @@ import { QueryExpression } from './query-expression';
 
 /**
  * Queries are used to extract data from a source.
+ *
+ * Each query's `expressions` must be a query expression or an array of
+ * expressions. This distinction allows for a clear distinction between queries
+ * that return singular vs. arrayed results.
  */
 export interface Query<QE extends QueryExpression> {
   id: string;
-  expressions: QE[];
+  expressions: QE | QE[];
   options?: RequestOptions;
 }
 
@@ -51,7 +55,7 @@ export function buildQuery<QE extends QueryExpression, QB = unknown>(
     );
   } else {
     let query = queryOrExpressions as Query<QE>;
-    let expressions: QE[];
+    let expressions: QE | QE[];
     let options: RequestOptions | undefined;
     let id: string;
 
@@ -73,13 +77,13 @@ export function buildQuery<QE extends QueryExpression, QB = unknown>(
     } else {
       if (Array.isArray(queryOrExpressions)) {
         expressions = [];
-        for (let queryOrExpression of queryOrExpressions) {
-          expressions.push(toQueryExpression<QE>(queryOrExpression));
+        for (let qe of queryOrExpressions) {
+          expressions.push(toQueryExpression<QE>(qe));
         }
       } else {
-        expressions = [
-          toQueryExpression(queryOrExpressions as QE | QueryTerm<QE>)
-        ];
+        expressions = toQueryExpression(
+          queryOrExpressions as QE | QueryTerm<QE>
+        );
       }
       options = queryOptions;
       id = queryId ?? Orbit.uuid();
@@ -109,5 +113,5 @@ export function isQuery<
   QE extends QueryExpression = QueryExpression,
   QB = unknown
 >(query: QueryOrExpressions<QE, QB>): query is Query<QE> {
-  return Array.isArray((query as Query<QE>).expressions);
+  return (query as Query<QE>).expressions !== undefined;
 }
diff --git a/packages/@orbit/data/src/transform.ts b/packages/@orbit/data/src/transform.ts
index 7d18ddec2..f1e4568b7 100644
--- a/packages/@orbit/data/src/transform.ts
+++ b/packages/@orbit/data/src/transform.ts
@@ -21,7 +21,7 @@ export type TransformOrOperations<O extends Operation, TB> =
  */
 export interface Transform<O extends Operation> {
   id: string;
-  operations: O[];
+  operations: O | O[];
   options?: RequestOptions;
 }
 
@@ -55,7 +55,7 @@ export function buildTransform<O extends Operation, TB = unknown>(
     );
   } else {
     let transform = transformOrOperations as Transform<O>;
-    let operations: O[];
+    let operations: O | O[];
     let options: RequestOptions | undefined;
     let id: string;
 
@@ -77,11 +77,11 @@ export function buildTransform<O extends Operation, TB = unknown>(
     } else {
       if (Array.isArray(transformOrOperations)) {
         operations = [];
-        for (let transformOrOperation of transformOrOperations) {
-          operations.push(toOperation<O>(transformOrOperation));
+        for (let o of transformOrOperations) {
+          operations.push(toOperation<O>(o));
         }
       } else {
-        operations = [toOperation<O>(transformOrOperations as O)];
+        operations = toOperation<O>(transformOrOperations as O);
       }
       options = transformOptions;
       id = transformId ?? Orbit.uuid();
@@ -110,5 +110,5 @@ function isOperationTerm<O extends Operation = Operation>(
 function isTransform<O extends Operation = Operation>(
   transform: TransformOrOperations<O, unknown>
 ): transform is Transform<O> {
-  return Array.isArray((transform as Transform<O>).operations);
+  return (transform as Transform<O>).operations !== undefined;
 }
diff --git a/packages/@orbit/data/test/query-test.ts b/packages/@orbit/data/test/query-test.ts
index d799e0f2c..13d4934ce 100644
--- a/packages/@orbit/data/test/query-test.ts
+++ b/packages/@orbit/data/test/query-test.ts
@@ -39,9 +39,9 @@ module('buildQuery', function () {
 
     assert.strictEqual(query.id, 'abc123', 'id was populated');
     assert.strictEqual(
-      query.expressions[0],
+      query.expressions,
       expression,
-      'expression was populated'
+      'expressions was populated'
     );
     assert.strictEqual(query.options, options, 'options was populated');
   });
@@ -53,13 +53,13 @@ module('buildQuery', function () {
     };
     let expressions = [expression];
     let options = { sources: { jsonapi: { include: 'comments' } } };
-    let query = buildQuery(expression, options, 'abc123');
+    let query = buildQuery(expressions, options, 'abc123');
 
     assert.strictEqual(query.id, 'abc123', 'id was populated');
     assert.deepEqual(
       query.expressions,
       expressions,
-      'expression was populated'
+      'expressions was populated'
     );
     assert.strictEqual(query.options, options, 'options was populated');
   });
@@ -76,8 +76,8 @@ module('buildQuery', function () {
     assert.strictEqual(query.id, 'abc123', 'id was populated');
     assert.deepEqual(
       query.expressions,
-      [{ op: 'findRecords', type: 'planet' }],
-      'expression was populated'
+      { op: 'findRecords', type: 'planet' },
+      'expressions was populated'
     );
     assert.strictEqual(query.options, options, 'options was populated');
   });
@@ -108,7 +108,7 @@ module('buildQuery', function () {
         { op: 'findRecords', type: 'planet' },
         { op: 'findRecords', type: 'moon' }
       ],
-      'expression was populated'
+      'expressions was populated'
     );
     assert.strictEqual(query.options, options, 'options was populated');
   });
@@ -131,12 +131,10 @@ module('buildQuery', function () {
     let query2 = buildQuery(query1, { a: '2', b: '2' }, '2');
     assert.notStrictEqual(query1, query2);
     assert.deepEqual(query2, {
-      expressions: [
-        {
-          op: 'findRecords',
-          type: 'planet'
-        }
-      ],
+      expressions: {
+        op: 'findRecords',
+        type: 'planet'
+      },
       options: {
         a: '2',
         b: '2',
@@ -160,8 +158,8 @@ module('buildQuery', function () {
     );
     assert.deepEqual(
       query.expressions,
-      [expression],
-      'expression was populated'
+      expression,
+      'expressions was populated'
     );
   });
 
@@ -173,9 +171,9 @@ module('buildQuery', function () {
     let queryFactory = new QueryTerm(expression);
     let query = buildQuery<RecordQueryExpression>(queryFactory);
     assert.strictEqual(
-      query.expressions[0],
+      query.expressions,
       expression,
-      'expression was populated'
+      'expressions was populated'
     );
   });
 
@@ -189,15 +187,8 @@ module('buildQuery', function () {
       type: 'moon'
     };
     let query = buildQuery<RecordQueryExpression>([expression1, expression2]);
-    assert.strictEqual(
-      query.expressions[0],
-      expression1,
-      'expression1 was populated'
-    );
-    assert.strictEqual(
-      query.expressions[1],
-      expression2,
-      'expression2 was populated'
-    );
+    let qe = query.expressions as RecordQueryExpression[];
+    assert.strictEqual(qe[0], expression1, 'expression1 was populated');
+    assert.strictEqual(qe[1], expression2, 'expression2 was populated');
   });
 });
diff --git a/packages/@orbit/data/test/source-interfaces/pullable-test.ts b/packages/@orbit/data/test/source-interfaces/pullable-test.ts
index b476c6a68..61a761c20 100644
--- a/packages/@orbit/data/test/source-interfaces/pullable-test.ts
+++ b/packages/@orbit/data/test/source-interfaces/pullable-test.ts
@@ -96,7 +96,7 @@ module('@pullable', function (hooks) {
 
     source._pull = async function (query) {
       assert.equal(++order, 1, 'action performed after willPull');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return fullResponse;
     };
 
@@ -116,7 +116,7 @@ module('@pullable', function (hooks) {
         2,
         'pull triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.strictEqual(result, fullResponse, 'result matches');
     });
 
@@ -162,7 +162,7 @@ module('@pullable', function (hooks) {
 
     source._pull = async function (query) {
       assert.equal(++order, 4, 'action performed after willPull');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return fullResponse;
     };
 
@@ -182,7 +182,7 @@ module('@pullable', function (hooks) {
         5,
         'pull triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.strictEqual(result, fullResponse, 'result matches');
     });
 
@@ -226,7 +226,7 @@ module('@pullable', function (hooks) {
         3,
         'pullFail triggered after an unsuccessful beforePull'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.equal(error, ':(', 'error matches');
     });
 
@@ -246,7 +246,7 @@ module('@pullable', function (hooks) {
 
     source._pull = function (query) {
       assert.equal(++order, 1, 'action performed after willPull');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return Promise.reject(':(');
     };
 
@@ -256,7 +256,7 @@ module('@pullable', function (hooks) {
 
     source.on('pullFail', (query, error) => {
       assert.equal(++order, 2, 'pullFail triggered after an unsuccessful pull');
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.equal(error, ':(', 'error matches');
     });
 
@@ -385,7 +385,7 @@ module('@pullable', function (hooks) {
 
     source._pull = async function (query) {
       assert.equal(++order, 1, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return fullResponse;
     };
 
@@ -395,7 +395,7 @@ module('@pullable', function (hooks) {
         2,
         'pull triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.deepEqual(result, fullResponse, 'result matches');
     });
 
@@ -444,14 +444,14 @@ module('@pullable', function (hooks) {
 
     source.on('beforePull', async (query) => {
       assert.equal(++order, 1, 'beforePull triggered first');
-      assert.strictEqual(query.expressions[0], qe, 'beforePull: query matches');
+      assert.strictEqual(query.expressions, qe, 'beforePull: query matches');
 
       return ['remote', { details: details1 }];
     });
 
     source._pull = async function (query) {
       assert.equal(++order, 2, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, '_pull: query matches');
+      assert.strictEqual(query.expressions, qe, '_pull: query matches');
       return {
         transforms: transforms1,
         details: details1
@@ -464,7 +464,7 @@ module('@pullable', function (hooks) {
         3,
         'pull triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'pull: query matches');
+      assert.strictEqual(query.expressions, qe, 'pull: query matches');
       assert.deepEqual(result, expectedResult, 'pull: result matches');
     });
 
diff --git a/packages/@orbit/data/test/source-interfaces/queryable-test.ts b/packages/@orbit/data/test/source-interfaces/queryable-test.ts
index edb35055a..795cbd3ca 100644
--- a/packages/@orbit/data/test/source-interfaces/queryable-test.ts
+++ b/packages/@orbit/data/test/source-interfaces/queryable-test.ts
@@ -90,7 +90,7 @@ module('@queryable', function (hooks) {
 
     source._query = async function (query) {
       assert.equal(++order, 1, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return fullResponse;
     };
 
@@ -100,7 +100,7 @@ module('@queryable', function (hooks) {
         2,
         'query triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.strictEqual(result, fullResponse, 'result matches');
     });
 
@@ -121,7 +121,7 @@ module('@queryable', function (hooks) {
 
     source._query = async function (query) {
       assert.equal(++order, 1, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return fullResponse;
     };
 
@@ -131,7 +131,7 @@ module('@queryable', function (hooks) {
         2,
         'query triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.equal(result, fullResponse, 'result matches');
     });
 
@@ -157,7 +157,7 @@ module('@queryable', function (hooks) {
 
     source._query = async function (query) {
       assert.equal(++order, 1, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return fullResponse;
     };
 
@@ -167,7 +167,7 @@ module('@queryable', function (hooks) {
         2,
         'query triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.deepEqual(result, fullResponse, 'result matches');
     });
 
@@ -185,7 +185,7 @@ module('@queryable', function (hooks) {
 
     source._query = function (query) {
       assert.equal(++order, 1, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return Promise.reject(':(');
     };
 
@@ -199,7 +199,7 @@ module('@queryable', function (hooks) {
         2,
         'queryFail triggered after an unsuccessful query'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.equal(error, ':(', 'error matches');
     });
 
@@ -403,7 +403,7 @@ module('@queryable', function (hooks) {
     ];
     source._query = async function (query) {
       assert.equal(++order, 1, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, 'query object matches');
+      assert.strictEqual(query.expressions, qe, 'query object matches');
       return { data: result1 };
     };
 
@@ -413,7 +413,7 @@ module('@queryable', function (hooks) {
         2,
         'query triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query matches');
+      assert.strictEqual(query.expressions, qe, 'query matches');
       assert.deepEqual(result, { data: result1 }, 'result matches');
     });
 
@@ -452,18 +452,14 @@ module('@queryable', function (hooks) {
 
     source.on('beforeQuery', async (query) => {
       assert.equal(++order, 1, 'beforeQuery triggered first');
-      assert.strictEqual(
-        query.expressions[0],
-        qe,
-        'beforeQuery: query matches'
-      );
+      assert.strictEqual(query.expressions, qe, 'beforeQuery: query matches');
 
       return ['remote', { details: details1 }];
     });
 
     source._query = async function (query) {
       assert.equal(++order, 2, 'action performed after beforeQuery');
-      assert.strictEqual(query.expressions[0], qe, '_query: query matches');
+      assert.strictEqual(query.expressions, qe, '_query: query matches');
       return { data: data1, details: details1 };
     };
 
@@ -473,7 +469,7 @@ module('@queryable', function (hooks) {
         3,
         'query triggered after action performed successfully'
       );
-      assert.strictEqual(query.expressions[0], qe, 'query: query matches');
+      assert.strictEqual(query.expressions, qe, 'query: query matches');
       assert.deepEqual(result, expectedResult, 'result matches');
     });
 
diff --git a/packages/@orbit/data/test/source-interfaces/syncable-test.ts b/packages/@orbit/data/test/source-interfaces/syncable-test.ts
index 823058e14..6e426d81f 100644
--- a/packages/@orbit/data/test/source-interfaces/syncable-test.ts
+++ b/packages/@orbit/data/test/source-interfaces/syncable-test.ts
@@ -106,7 +106,7 @@ module('@syncable', function (hooks) {
   });
 
   test('#sync can accept a transform builder function, create a transform, and call internal method `_sync`', async function (assert) {
-    assert.expect(4);
+    assert.expect(2);
 
     const earth = { type: 'planet', id: 'earth' };
     const jupiter = { type: 'planet', id: 'jupiter' };
@@ -115,26 +115,19 @@ module('@syncable', function (hooks) {
     source._sync = async function (transform: Transform<RecordOperation>) {
       order++;
       if (order === 1) {
-        assert.strictEqual(
-          transform.operations.length,
-          2,
-          'transform passed to _sync with correct operations count'
-        );
-        assert.deepEqual(
-          transform.operations[0],
-          {
-            op: 'addRecord',
-            record: earth
-          },
-          'expected operation'
-        );
         assert.deepEqual(
-          transform.operations[1],
-          {
-            op: 'addRecord',
-            record: jupiter
-          },
-          'expected operation'
+          transform.operations as RecordOperation[],
+          [
+            {
+              op: 'addRecord',
+              record: earth
+            },
+            {
+              op: 'addRecord',
+              record: jupiter
+            }
+          ],
+          'transform passed to _sync with correct data'
         );
       } else {
         assert.ok(false, 'unexpected');
diff --git a/packages/@orbit/data/test/source-interfaces/updatable-test.ts b/packages/@orbit/data/test/source-interfaces/updatable-test.ts
index 5fbbdf9b0..05a108551 100644
--- a/packages/@orbit/data/test/source-interfaces/updatable-test.ts
+++ b/packages/@orbit/data/test/source-interfaces/updatable-test.ts
@@ -137,24 +137,21 @@ module('@updatable', function (hooks) {
   });
 
   test('#update can accept a transform builder function', async function (assert) {
-    assert.expect(3);
+    assert.expect(2);
 
     const earth = { type: 'planet', id: 'earth' };
     const fullResponse = { data: earth, transforms: [] };
 
     source._update = async function (transform: Transform<RecordOperation>) {
-      assert.strictEqual(
-        transform.operations.length,
-        1,
-        'transform passed to _update with correct operations count'
-      );
       assert.deepEqual(
-        transform.operations[0],
-        {
-          op: 'addRecord',
-          record: earth
-        },
-        'expected operation'
+        transform.operations as RecordOperation[],
+        [
+          {
+            op: 'addRecord',
+            record: earth
+          }
+        ],
+        'transform passed to _update with correct operations'
       );
       return fullResponse;
     };
diff --git a/packages/@orbit/data/test/transform-test.ts b/packages/@orbit/data/test/transform-test.ts
index b070233ac..d115d1a76 100644
--- a/packages/@orbit/data/test/transform-test.ts
+++ b/packages/@orbit/data/test/transform-test.ts
@@ -142,7 +142,7 @@ module('buildTransform', function () {
     );
     assert.deepEqual(
       transform.operations,
-      [operation],
+      operation,
       'operations was populated'
     );
   });
diff --git a/packages/@orbit/indexeddb/src/indexeddb-source.ts b/packages/@orbit/indexeddb/src/indexeddb-source.ts
index 564b79b40..edd10a87b 100644
--- a/packages/@orbit/indexeddb/src/indexeddb-source.ts
+++ b/packages/@orbit/indexeddb/src/indexeddb-source.ts
@@ -212,7 +212,12 @@ export class IndexedDBSource<
     }
 
     if (hints?.data) {
-      if (transform.operations.length > 1 && Array.isArray(hints.data)) {
+      if (Array.isArray(transform.operations)) {
+        assert(
+          'IndexedDBSource#update: `hints.data` must be an array if `transform.operations` is an array',
+          Array.isArray(hints.data)
+        );
+
         const responseData = [];
         const hintsData = hints.data as RecordOperationResult[];
         for (let h of hintsData) {
@@ -225,11 +230,7 @@ export class IndexedDBSource<
         );
       }
     } else if (results) {
-      if (transform.operations.length === 1 && Array.isArray(results)) {
-        response.data = results[0];
-      } else {
-        response.data = results;
-      }
+      response.data = results;
     }
 
     if (hints?.details) {
@@ -251,7 +252,12 @@ export class IndexedDBSource<
 
     if (hints?.data) {
       response = {};
-      if (query.expressions.length > 1 && Array.isArray(hints.data)) {
+      if (Array.isArray(query.expressions)) {
+        assert(
+          'IndexedDBSource#query: `hints.data` must be an array if `query.expressions` is an array',
+          Array.isArray(hints.data)
+        );
+
         const responseData = [];
         const hintsData = hints.data as RecordQueryExpressionResult[];
         for (let h of hintsData) {
@@ -305,15 +311,15 @@ export class IndexedDBSource<
 
     const results = await this._cache.query(query);
 
-    if (query.expressions.length === 1) {
-      operations = this._operationsFromQueryResult(
-        results as RecordQueryExpressionResult
-      );
-    } else {
+    if (Array.isArray(query.expressions)) {
       operations = [];
       for (let result of results as RecordQueryExpressionResult[]) {
         operations.push(...this._operationsFromQueryResult(result));
       }
+    } else {
+      operations = this._operationsFromQueryResult(
+        results as RecordQueryExpressionResult
+      );
     }
 
     fullResponse.transforms = [buildTransform(operations)];
diff --git a/packages/@orbit/indexeddb/test/indexeddb-cache-update-test.ts b/packages/@orbit/indexeddb/test/indexeddb-cache-update-test.ts
index 1ed1f1ead..516ceafce 100644
--- a/packages/@orbit/indexeddb/test/indexeddb-cache-update-test.ts
+++ b/packages/@orbit/indexeddb/test/indexeddb-cache-update-test.ts
@@ -992,13 +992,12 @@ module('IndexedDBCache - update', function (hooks) {
           ]);
 
           let result = await cache.update(
-            (t) => [
+            (t) =>
               t.updateRecord({
                 type: 'planet',
                 id: '1',
                 attributes: { classification: 'terrestrial' }
-              })
-            ],
+              }),
             { fullResponse: true }
           );
 
@@ -1072,21 +1071,20 @@ module('IndexedDBCache - update', function (hooks) {
         test('#update can replace related records but only if they are different', async function (assert) {
           const tb = cache.transformBuilder;
 
-          await cache.update((t) => [
+          await cache.update((t) =>
             t.addRecord({
               type: 'planet',
               id: '1',
               attributes: { name: 'Earth' },
               relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
             })
-          ]);
+          );
 
           let result = await cache.update(
-            (t) => [
+            (t) =>
               t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
                 { type: 'moon', id: 'm1' }
-              ])
-            ],
+              ]),
             { fullResponse: true }
           );
 
@@ -1233,7 +1231,7 @@ module('IndexedDBCache - update', function (hooks) {
             relationships: { moons: { data: [{ type: 'moon', id: 'm2' }] } }
           };
 
-          let result = await cache.update([tb.addRecord(earth)], {
+          let result = await cache.update(tb.addRecord(earth), {
             fullResponse: true
           });
 
@@ -1292,7 +1290,7 @@ module('IndexedDBCache - update', function (hooks) {
             'addRecord full response is correct'
           );
 
-          result = await cache.update([tb.updateRecord(jupiter)], {
+          result = await cache.update(tb.updateRecord(jupiter), {
             fullResponse: true
           });
 
@@ -1376,7 +1374,7 @@ module('IndexedDBCache - update', function (hooks) {
           const tb = cache.transformBuilder;
 
           let result = await cache.update(
-            (t) => [t.addRecord({ id: '1', type: 'planet' })],
+            (t) => t.addRecord({ id: '1', type: 'planet' }),
             { fullResponse: true }
           );
 
@@ -1413,15 +1411,14 @@ module('IndexedDBCache - update', function (hooks) {
           );
 
           result = await cache.update(
-            (t) => [
+            (t) =>
               t.updateRecord({
                 id: '1',
                 type: 'planet',
                 relationships: {
                   moons: { data: [] }
                 }
-              })
-            ],
+              }),
             { fullResponse: true }
           );
 
diff --git a/packages/@orbit/indexeddb/test/indexeddb-source-pullable-test.ts b/packages/@orbit/indexeddb/test/indexeddb-source-pullable-test.ts
index e7e661b52..74421b534 100644
--- a/packages/@orbit/indexeddb/test/indexeddb-source-pullable-test.ts
+++ b/packages/@orbit/indexeddb/test/indexeddb-source-pullable-test.ts
@@ -2,6 +2,7 @@ import {
   AddRecordOperation,
   InitializedRecord,
   RecordKeyMap,
+  RecordOperation,
   RecordSchema,
   RecordTransform
 } from '@orbit/records';
@@ -120,7 +121,7 @@ module('IndexedDBSource - pullable', function (hooks) {
 
     assert.equal(transforms.length, 1, 'one transform returned');
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord', 'updateRecord', 'updateRecord'],
       'operations match expectations'
     );
@@ -186,12 +187,12 @@ module('IndexedDBSource - pullable', function (hooks) {
       'log contains transform'
     );
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord', 'updateRecord'],
       'operations match expectations'
     );
     assert.deepEqual(
-      transforms[0].operations.map(
+      (transforms[0].operations as RecordOperation[]).map(
         (o) => (o as AddRecordOperation)?.record?.type
       ),
       ['planet', 'planet'],
@@ -244,12 +245,12 @@ module('IndexedDBSource - pullable', function (hooks) {
       'log contains transform'
     );
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord', 'updateRecord'],
       'operations match expectations'
     );
     assert.deepEqual(
-      transforms[0].operations.map(
+      (transforms[0].operations as RecordOperation[]).map(
         (o) => (o as AddRecordOperation).record.type
       ),
       ['planet', 'moon'],
@@ -308,7 +309,7 @@ module('IndexedDBSource - pullable', function (hooks) {
       'log contains transform'
     );
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord'],
       'operations match expectations'
     );
diff --git a/packages/@orbit/indexeddb/test/indexeddb-source-queryable-test.ts b/packages/@orbit/indexeddb/test/indexeddb-source-queryable-test.ts
index a03f84837..486bbf3fa 100644
--- a/packages/@orbit/indexeddb/test/indexeddb-source-queryable-test.ts
+++ b/packages/@orbit/indexeddb/test/indexeddb-source-queryable-test.ts
@@ -107,9 +107,7 @@ module('IndexedDBSource - queryable', function (hooks) {
     };
 
     source.on('beforeQuery', (query: RecordQuery, hints: any) => {
-      if (query.expressions[0].op === 'findRecord') {
-        hints.data = jupiter2;
-      }
+      hints.data = jupiter2;
     });
 
     await source.cache.update((t) => t.addRecord(jupiter2));
@@ -149,10 +147,7 @@ module('IndexedDBSource - queryable', function (hooks) {
     };
 
     source.on('beforeQuery', (query: RecordQuery, hints: any) => {
-      if (
-        query.expressions[0].op === 'findRecords' &&
-        query.options?.sources?.remote.customFilter === 'distantPlanets'
-      ) {
+      if (query.options?.sources?.remote.customFilter === 'distantPlanets') {
         hints.data = [
           { type: 'planet', id: 'uranus' },
           { type: 'planet', id: 'jupiter' }
diff --git a/packages/@orbit/jsonapi/src/lib/query-requests.ts b/packages/@orbit/jsonapi/src/lib/query-requests.ts
index 5ee19a3cd..3a46437ae 100644
--- a/packages/@orbit/jsonapi/src/lib/query-requests.ts
+++ b/packages/@orbit/jsonapi/src/lib/query-requests.ts
@@ -1,4 +1,4 @@
-import { Dict } from '@orbit/utils';
+import { Dict, toArray } from '@orbit/utils';
 import {
   RecordQuery,
   AddToRelatedRecordsOperation,
@@ -78,7 +78,7 @@ export function getQueryRequests(
 ): RecordQueryRequest[] {
   const requests: RecordQueryRequest[] = [];
 
-  for (let expression of query.expressions) {
+  for (let expression of toArray(query.expressions)) {
     let request = ExpressionToRequestMap[expression.op](
       expression as RecordQueryExpression,
       requestProcessor
diff --git a/packages/@orbit/jsonapi/src/lib/transform-requests.ts b/packages/@orbit/jsonapi/src/lib/transform-requests.ts
index 118baf22d..f8182bb00 100644
--- a/packages/@orbit/jsonapi/src/lib/transform-requests.ts
+++ b/packages/@orbit/jsonapi/src/lib/transform-requests.ts
@@ -1,4 +1,4 @@
-import { clone, deepSet, Dict } from '@orbit/utils';
+import { clone, deepSet, Dict, toArray } from '@orbit/utils';
 import {
   cloneRecordIdentity,
   equalRecordIdentities,
@@ -317,80 +317,75 @@ export function getTransformRequests(
   transform: RecordTransform
 ): RecordTransformRequest[] {
   const requests: RecordTransformRequest[] = [];
-  let prevRequest: RecordTransformRequest | null;
-
-  (transform.operations as RecordOperation[]).forEach(
-    (operation: RecordOperation) => {
-      let request;
-      let newRequestNeeded = true;
-
-      if (
-        prevRequest &&
-        equalRecordIdentities(prevRequest.record, operation.record)
+  let prevRequest: RecordTransformRequest | null = null;
+
+  for (let operation of toArray(transform.operations)) {
+    let request;
+    let newRequestNeeded = true;
+
+    if (
+      prevRequest &&
+      equalRecordIdentities(prevRequest.record, operation.record)
+    ) {
+      if (operation.op === 'removeRecord') {
+        newRequestNeeded = false;
+
+        if (prevRequest.op !== 'removeRecord') {
+          prevRequest = null;
+          requests.pop();
+        }
+      } else if (
+        prevRequest.op === 'addRecord' ||
+        prevRequest.op === 'updateRecord'
       ) {
-        if (operation.op === 'removeRecord') {
+        if (operation.op === 'replaceAttribute') {
           newRequestNeeded = false;
-
-          if (prevRequest.op !== 'removeRecord') {
-            prevRequest = null;
-            requests.pop();
-          }
-        } else if (
-          prevRequest.op === 'addRecord' ||
-          prevRequest.op === 'updateRecord'
-        ) {
-          if (operation.op === 'replaceAttribute') {
-            newRequestNeeded = false;
-            replaceRecordAttribute(
-              prevRequest.record,
-              operation.attribute,
-              operation.value
-            );
-          } else if (operation.op === 'replaceRelatedRecord') {
-            newRequestNeeded = false;
-            replaceRecordHasOne(
-              prevRequest.record,
-              operation.relationship,
-              operation.relatedRecord as RecordIdentity
-            );
-          } else if (operation.op === 'replaceRelatedRecords') {
-            newRequestNeeded = false;
-            replaceRecordHasMany(
-              prevRequest.record,
-              operation.relationship,
-              operation.relatedRecords
-            );
-          }
-        } else if (
-          prevRequest.op === 'addToRelatedRecords' &&
-          operation.op === 'addToRelatedRecords' &&
-          (prevRequest as AddToRelatedRecordsRequest).relationship ===
-            operation.relationship
-        ) {
+          replaceRecordAttribute(
+            prevRequest.record,
+            operation.attribute,
+            operation.value
+          );
+        } else if (operation.op === 'replaceRelatedRecord') {
+          newRequestNeeded = false;
+          replaceRecordHasOne(
+            prevRequest.record,
+            operation.relationship,
+            operation.relatedRecord as RecordIdentity
+          );
+        } else if (operation.op === 'replaceRelatedRecords') {
           newRequestNeeded = false;
-          (prevRequest as AddToRelatedRecordsRequest).relatedRecords.push(
-            cloneRecordIdentity(operation.relatedRecord)
+          replaceRecordHasMany(
+            prevRequest.record,
+            operation.relationship,
+            operation.relatedRecords
           );
         }
+      } else if (
+        prevRequest.op === 'addToRelatedRecords' &&
+        operation.op === 'addToRelatedRecords' &&
+        (prevRequest as AddToRelatedRecordsRequest).relationship ===
+          operation.relationship
+      ) {
+        newRequestNeeded = false;
+        (prevRequest as AddToRelatedRecordsRequest).relatedRecords.push(
+          cloneRecordIdentity(operation.relatedRecord)
+        );
       }
+    }
 
-      if (newRequestNeeded) {
-        request = OperationToRequestMap[operation.op](operation);
-      }
+    if (newRequestNeeded) {
+      request = OperationToRequestMap[operation.op](operation);
+    }
 
-      if (request) {
-        let options = requestProcessor.customRequestOptions(
-          transform,
-          operation
-        );
-        if (options) {
-          request.options = options;
-        }
-        requests.push(request);
-        prevRequest = request;
+    if (request) {
+      let options = requestProcessor.customRequestOptions(transform, operation);
+      if (options) {
+        request.options = options;
       }
+      requests.push(request);
+      prevRequest = request;
     }
-  );
+  }
 
   return requests;
 }
diff --git a/packages/@orbit/jsonapi/test/jsonapi-source-pullable-test.ts b/packages/@orbit/jsonapi/test/jsonapi-source-pullable-test.ts
index 456344bca..7a4dcae9d 100644
--- a/packages/@orbit/jsonapi/test/jsonapi-source-pullable-test.ts
+++ b/packages/@orbit/jsonapi/test/jsonapi-source-pullable-test.ts
@@ -12,6 +12,7 @@ import {
 } from '@orbit/records';
 import * as sinon from 'sinon';
 import { SinonStub } from 'sinon';
+import { toArray } from '@orbit/utils';
 import {
   JSONAPIResourceIdentitySerializer,
   JSONAPIResourceSerializer,
@@ -83,11 +84,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter']
@@ -289,11 +290,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Earth', 'Saturn']
@@ -350,11 +351,11 @@ module('JSONAPISource - pullable', function (hooks) {
 
       assert.equal(transforms.length, 1, 'one transform returned');
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Earth']
@@ -404,11 +405,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Earth']
@@ -453,11 +454,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Moon']
@@ -525,11 +526,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Moon', 'Phobos', 'Deimos']
@@ -587,11 +588,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Mars']
@@ -637,11 +638,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Earth', 'Jupiter', 'Saturn']
@@ -687,11 +688,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Saturn', 'Jupiter', 'Earth']
@@ -749,11 +750,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Saturn', 'Earth']
@@ -803,11 +804,11 @@ module('JSONAPISource - pullable', function (hooks) {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Earth', 'Saturn']
@@ -867,12 +868,14 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Earth');
 
@@ -924,12 +927,14 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Earth');
 
@@ -980,12 +985,14 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Moon');
 
@@ -1055,8 +1062,10 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -1067,9 +1076,9 @@ module('JSONAPISource - pullable', function (hooks) {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -1132,12 +1141,14 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Mars');
 
@@ -1185,8 +1196,10 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -1197,9 +1210,9 @@ module('JSONAPISource - pullable', function (hooks) {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -1250,8 +1263,10 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -1262,9 +1277,9 @@ module('JSONAPISource - pullable', function (hooks) {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -1331,8 +1346,10 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -1343,9 +1360,9 @@ module('JSONAPISource - pullable', function (hooks) {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -1402,8 +1419,10 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -1414,9 +1433,9 @@ module('JSONAPISource - pullable', function (hooks) {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -1573,15 +1592,17 @@ module('JSONAPISource - pullable', function (hooks) {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'replaceRelatedRecords']
       );
 
-      const op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      const op1 = ops[0] as UpdateRecordOperation;
       assert.equal(op1.record.attributes?.name, 'Io');
 
-      const op2 = transforms[0].operations[1] as ReplaceRelatedRecordsOperation;
+      const op2 = ops[1] as ReplaceRelatedRecordsOperation;
       assert.equal(op2.record.id, planet.id);
       assert.equal(op2.relationship, 'moons');
       assert.deepEqual(
@@ -1671,11 +1692,11 @@ module('JSONAPISource - pullable', function (hooks) {
       assert.equal(transforms.length, 1, 'one transform returned');
 
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Earth']
@@ -1726,22 +1747,22 @@ module('JSONAPISource - pullable', function (hooks) {
       assert.equal(transforms.length, 2, 'two transforms returned');
 
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Earth']
       );
 
       assert.deepEqual(
-        transforms[1].operations.map((o) => o.op),
+        toArray(transforms[1].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[1].operations.map(
+        toArray(transforms[1].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Io', 'Europa']
diff --git a/packages/@orbit/jsonapi/test/jsonapi-source-pushable-test.ts b/packages/@orbit/jsonapi/test/jsonapi-source-pushable-test.ts
index c2db675b9..eb50747a8 100644
--- a/packages/@orbit/jsonapi/test/jsonapi-source-pushable-test.ts
+++ b/packages/@orbit/jsonapi/test/jsonapi-source-pushable-test.ts
@@ -14,6 +14,7 @@ import {
   RecordTransform,
   UpdateRecordOperation
 } from '@orbit/records';
+import { toArray } from '@orbit/utils';
 import * as sinon from 'sinon';
 import { SinonStub } from 'sinon';
 import { JSONAPIResourceSerializer } from '../src';
@@ -90,7 +91,7 @@ module('JSONAPISource - pushable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -220,7 +221,7 @@ module('JSONAPISource - pushable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -231,7 +232,7 @@ module('JSONAPISource - pushable', function (hooks) {
             'transform event then returns add-remote-id op'
           );
         } else if (transformCount === 3) {
-          let operationsWithoutId = transform.operations.map((op) => {
+          let operationsWithoutId = toArray(transform.operations).map((op) => {
             let clonedOp = Object.assign({}, op) as RecordOperation;
             delete (clonedOp as any).record.id;
             return clonedOp;
@@ -363,7 +364,7 @@ module('JSONAPISource - pushable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [replacePlanetOp],
+            replacePlanetOp,
             'transform event initially returns replace-record op'
           );
         }
@@ -486,7 +487,7 @@ module('JSONAPISource - pushable', function (hooks) {
       )) as RecordTransform[];
 
       assert.deepEqual(
-        transforms[1].operations.map((o) => o.op),
+        toArray(transforms[1].operations).map((o) => o.op),
         ['replaceAttribute', 'replaceKey']
       );
       const ops = transforms[1].operations as ReplaceKeyOperation[];
@@ -1021,7 +1022,7 @@ module('JSONAPISource - pushable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         }
diff --git a/packages/@orbit/jsonapi/test/jsonapi-source-updatable-test.ts b/packages/@orbit/jsonapi/test/jsonapi-source-updatable-test.ts
index 85b306d7a..c1bc01431 100644
--- a/packages/@orbit/jsonapi/test/jsonapi-source-updatable-test.ts
+++ b/packages/@orbit/jsonapi/test/jsonapi-source-updatable-test.ts
@@ -9,6 +9,7 @@ import {
   AddRecordOperation,
   UpdateRecordOperation
 } from '@orbit/records';
+import { toArray } from '@orbit/utils';
 import * as sinon from 'sinon';
 import { SinonStub } from 'sinon';
 import { JSONAPIResourceSerializer } from '../src';
@@ -85,7 +86,7 @@ module('JSONAPISource - updatable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -186,7 +187,7 @@ module('JSONAPISource - updatable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -197,7 +198,7 @@ module('JSONAPISource - updatable', function (hooks) {
             'transform event then returns add-remote-id op'
           );
         } else if (transformCount === 3) {
-          let operationsWithoutId = transform.operations.map((op) => {
+          let operationsWithoutId = toArray(transform.operations).map((op) => {
             let clonedOp = Object.assign({}, op) as RecordOperation;
             delete (clonedOp as any).record.id;
             return clonedOp;
@@ -294,7 +295,7 @@ module('JSONAPISource - updatable', function (hooks) {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [replacePlanetOp],
+            replacePlanetOp,
             'transform event initially returns replace-record op'
           );
         }
@@ -422,11 +423,13 @@ module('JSONAPISource - updatable', function (hooks) {
       );
 
       assert.deepEqual(
-        transforms[1].operations.map((o) => o.op),
+        toArray(transforms[1].operations).map((o) => o.op),
         ['replaceAttribute', 'replaceKey']
       );
       assert.deepEqual(
-        transforms[1].operations.map((o) => (o as ReplaceKeyOperation).value),
+        toArray(transforms[1].operations).map(
+          (o) => (o as ReplaceKeyOperation).value
+        ),
         ['Mars', 'remote-id-123']
       );
       assert.deepEqual(data, {
diff --git a/packages/@orbit/jsonapi/test/jsonapi-source-with-legacy-serializer-settings-test.ts b/packages/@orbit/jsonapi/test/jsonapi-source-with-legacy-serializer-settings-test.ts
index f2484cf5a..2070bfeef 100644
--- a/packages/@orbit/jsonapi/test/jsonapi-source-with-legacy-serializer-settings-test.ts
+++ b/packages/@orbit/jsonapi/test/jsonapi-source-with-legacy-serializer-settings-test.ts
@@ -19,6 +19,7 @@ import {
   ReplaceRelatedRecordsOperation,
   RecordTransform
 } from '@orbit/records';
+import { toArray } from '@orbit/utils';
 import { jsonapiResponse } from './support/jsonapi';
 import { JSONAPISource } from '../src/jsonapi-source';
 import { Resource, ResourceDocument } from '../src/resource-document';
@@ -249,7 +250,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -379,7 +380,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -390,7 +391,7 @@ module('JSONAPISource with legacy serialization settings', function () {
             'transform event then returns add-remote-id op'
           );
         } else if (transformCount === 3) {
-          let operationsWithoutId = transform.operations.map((op) => {
+          let operationsWithoutId = toArray(transform.operations).map((op) => {
             let clonedOp = Object.assign({}, op) as RecordOperation;
             delete (clonedOp as any).record.id;
             return clonedOp;
@@ -522,7 +523,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [replacePlanetOp],
+            replacePlanetOp,
             'transform event initially returns replace-record op'
           );
         }
@@ -645,11 +646,13 @@ module('JSONAPISource with legacy serialization settings', function () {
       )) as RecordTransform[];
 
       assert.deepEqual(
-        transforms[1].operations.map((o) => o.op),
+        toArray(transforms[1].operations).map((o) => o.op),
         ['replaceAttribute', 'replaceKey']
       );
       assert.deepEqual(
-        transforms[1].operations.map((o) => (o as ReplaceKeyOperation).value),
+        toArray(transforms[1].operations).map(
+          (o) => (o as ReplaceKeyOperation).value
+        ),
         ['Mars', 'remote-id-123']
       );
     });
@@ -1180,7 +1183,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -1281,7 +1284,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         } else if (transformCount === 2) {
@@ -1292,7 +1295,7 @@ module('JSONAPISource with legacy serialization settings', function () {
             'transform event then returns add-remote-id op'
           );
         } else if (transformCount === 3) {
-          let operationsWithoutId = transform.operations.map((op) => {
+          let operationsWithoutId = toArray(transform.operations).map((op) => {
             let clonedOp = Object.assign({}, op) as RecordOperation;
             delete (clonedOp as any).record.id;
             return clonedOp;
@@ -1389,7 +1392,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [replacePlanetOp],
+            replacePlanetOp,
             'transform event initially returns replace-record op'
           );
         }
@@ -1517,11 +1520,13 @@ module('JSONAPISource with legacy serialization settings', function () {
       );
 
       assert.deepEqual(
-        transforms[1].operations.map((o) => o.op),
+        toArray(transforms[1].operations).map((o) => o.op),
         ['replaceAttribute', 'replaceKey']
       );
       assert.deepEqual(
-        transforms[1].operations.map((o) => (o as ReplaceKeyOperation).value),
+        toArray(transforms[1].operations).map(
+          (o) => (o as ReplaceKeyOperation).value
+        ),
         ['Mars', 'remote-id-123']
       );
       assert.deepEqual(data, {
@@ -2058,11 +2063,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter']
@@ -2264,11 +2269,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Earth', 'Saturn']
@@ -2325,11 +2330,11 @@ module('JSONAPISource with legacy serialization settings', function () {
 
       assert.equal(transforms.length, 1, 'one transform returned');
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Earth']
@@ -2379,11 +2384,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Earth']
@@ -2428,11 +2433,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Moon']
@@ -2500,11 +2505,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Moon', 'Phobos', 'Deimos']
@@ -2562,11 +2567,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Mars']
@@ -2612,11 +2617,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Earth', 'Jupiter', 'Saturn']
@@ -2662,11 +2667,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Saturn', 'Jupiter', 'Earth']
@@ -2724,11 +2729,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Saturn', 'Earth']
@@ -2778,11 +2783,11 @@ module('JSONAPISource with legacy serialization settings', function () {
         'log contains transform'
       );
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        toArray(transforms[0].operations).map((o) => o.op),
         ['updateRecord', 'updateRecord', 'updateRecord']
       );
       assert.deepEqual(
-        transforms[0].operations.map(
+        toArray(transforms[0].operations).map(
           (o) => (o as UpdateRecordOperation).record.attributes?.name
         ),
         ['Jupiter', 'Earth', 'Saturn']
@@ -2842,12 +2847,14 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      const op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Earth');
 
@@ -2899,12 +2906,14 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      const op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Earth');
 
@@ -2955,12 +2964,14 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      const op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Moon');
 
@@ -3030,8 +3041,10 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -3042,9 +3055,9 @@ module('JSONAPISource with legacy serialization settings', function () {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -3107,12 +3120,14 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'addToRelatedRecords']
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      const op1 = ops[0] as UpdateRecordOperation;
 
       assert.equal(op1.record.attributes?.name, 'Mars');
 
@@ -3160,8 +3175,10 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -3172,9 +3189,9 @@ module('JSONAPISource with legacy serialization settings', function () {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -3225,8 +3242,10 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -3237,9 +3256,9 @@ module('JSONAPISource with legacy serialization settings', function () {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -3306,8 +3325,10 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -3318,9 +3339,9 @@ module('JSONAPISource with legacy serialization settings', function () {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -3377,8 +3398,10 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         [
           'updateRecord',
           'updateRecord',
@@ -3389,9 +3412,9 @@ module('JSONAPISource with legacy serialization settings', function () {
         ]
       );
 
-      let op1 = transforms[0].operations[0] as UpdateRecordOperation;
-      let op2 = transforms[0].operations[1] as UpdateRecordOperation;
-      let op3 = transforms[0].operations[2] as UpdateRecordOperation;
+      let op1 = ops[0] as UpdateRecordOperation;
+      let op2 = ops[1] as UpdateRecordOperation;
+      let op3 = ops[2] as UpdateRecordOperation;
 
       assert.deepEqual(
         [op1, op2, op3].map((o) => o.record.attributes?.name),
@@ -3548,15 +3571,17 @@ module('JSONAPISource with legacy serialization settings', function () {
         source.transformLog.contains(transforms[0].id),
         'log contains transform'
       );
+
+      const ops = transforms[0].operations as RecordOperation[];
       assert.deepEqual(
-        transforms[0].operations.map((o) => o.op),
+        ops.map((o) => o.op),
         ['updateRecord', 'replaceRelatedRecords']
       );
 
-      const op1 = transforms[0].operations[0] as UpdateRecordOperation;
+      const op1 = ops[0] as UpdateRecordOperation;
       assert.equal(op1.record.attributes?.name, 'Io');
 
-      const op2 = transforms[0].operations[1] as ReplaceRelatedRecordsOperation;
+      const op2 = ops[1] as ReplaceRelatedRecordsOperation;
       assert.equal(op2.record.id, planet.id);
       assert.equal(op2.relationship, 'moons');
       assert.deepEqual(
@@ -5144,7 +5169,7 @@ module('JSONAPISource with legacy serialization settings', function () {
         if (transformCount === 1) {
           assert.deepEqual(
             transform.operations,
-            [addPlanetOp],
+            addPlanetOp,
             'transform event initially returns add-record op'
           );
         }
diff --git a/packages/@orbit/local-storage/src/local-storage-cache.ts b/packages/@orbit/local-storage/src/local-storage-cache.ts
index 475db49c0..ed39d72bc 100644
--- a/packages/@orbit/local-storage/src/local-storage-cache.ts
+++ b/packages/@orbit/local-storage/src/local-storage-cache.ts
@@ -1,4 +1,3 @@
-/* eslint-disable valid-jsdoc */
 import { Orbit } from '@orbit/core';
 import {
   InitializedRecord,
diff --git a/packages/@orbit/local-storage/src/local-storage-source.ts b/packages/@orbit/local-storage/src/local-storage-source.ts
index ce5685222..db28f92de 100644
--- a/packages/@orbit/local-storage/src/local-storage-source.ts
+++ b/packages/@orbit/local-storage/src/local-storage-source.ts
@@ -215,7 +215,12 @@ export class LocalStorageSource<
     }
 
     if (hints?.data) {
-      if (transform.operations.length > 1 && Array.isArray(hints.data)) {
+      if (Array.isArray(transform.operations)) {
+        assert(
+          'LocalStorageSource#update: `hints.data` must be an array if `transform.operations` is an array',
+          Array.isArray(hints.data)
+        );
+
         response.data = (hints.data as RecordOperationResult[]).map((h) =>
           this._retrieveOperationResult(h)
         );
@@ -225,11 +230,7 @@ export class LocalStorageSource<
         );
       }
     } else if (results) {
-      if (transform.operations.length === 1 && Array.isArray(results)) {
-        response.data = results[0];
-      } else {
-        response.data = results;
-      }
+      response.data = results;
     }
 
     if (hints?.details) {
@@ -251,7 +252,12 @@ export class LocalStorageSource<
 
     if (hints?.data) {
       response = {};
-      if (query.expressions.length > 1 && Array.isArray(hints.data)) {
+      if (Array.isArray(query.expressions)) {
+        assert(
+          'LocalStorageSource#query: `hints.data` must be an array if `query.expressions` is an array',
+          Array.isArray(hints.data)
+        );
+
         response.data = (hints.data as RecordQueryExpressionResult[]).map((h) =>
           this._retrieveQueryExpressionResult(h)
         );
@@ -302,15 +308,15 @@ export class LocalStorageSource<
 
     const results = this._cache.query(query);
 
-    if (query.expressions.length === 1) {
-      operations = this._operationsFromQueryResult(
-        results as RecordQueryExpressionResult
-      );
-    } else {
+    if (Array.isArray(query.expressions)) {
       operations = [];
       for (let result of results as RecordQueryExpressionResult[]) {
         operations.push(...this._operationsFromQueryResult(result));
       }
+    } else {
+      operations = this._operationsFromQueryResult(
+        results as RecordQueryExpressionResult
+      );
     }
 
     fullResponse.transforms = [buildTransform(operations)];
diff --git a/packages/@orbit/local-storage/test/local-storage-cache-update-test.ts b/packages/@orbit/local-storage/test/local-storage-cache-update-test.ts
index 45b3eb11b..f5c3a5930 100644
--- a/packages/@orbit/local-storage/test/local-storage-cache-update-test.ts
+++ b/packages/@orbit/local-storage/test/local-storage-cache-update-test.ts
@@ -1226,23 +1226,22 @@ module('LocalStorageCache - update', function (hooks) {
         cache = new LocalStorageCache({ schema, keyMap });
         const tb = cache.transformBuilder;
 
-        cache.update((t) => [
+        cache.update((t) =>
           t.addRecord({
             type: 'planet',
             id: '1',
             attributes: { name: 'Earth' },
             relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
           })
-        ]);
+        );
 
         let result = cache.update(
-          (t) => [
+          (t) =>
             t.updateRecord({
               type: 'planet',
               id: '1',
               attributes: { classification: 'terrestrial' }
-            })
-          ],
+            }),
           { fullResponse: true }
         );
 
@@ -1317,21 +1316,20 @@ module('LocalStorageCache - update', function (hooks) {
         cache = new LocalStorageCache({ schema, keyMap });
         const tb = cache.transformBuilder;
 
-        cache.update((t) => [
+        cache.update((t) =>
           t.addRecord({
             type: 'planet',
             id: '1',
             attributes: { name: 'Earth' },
             relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
           })
-        ]);
+        );
 
         let result = cache.update(
-          (t) => [
+          (t) =>
             t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
               { type: 'moon', id: 'm1' }
-            ])
-          ],
+            ]),
           { fullResponse: true }
         );
 
@@ -1467,7 +1465,7 @@ module('LocalStorageCache - update', function (hooks) {
           relationships: { moons: { data: [{ type: 'moon', id: 'm2' }] } }
         };
 
-        let result = cache.update([tb.addRecord(earth)], {
+        let result = cache.update(tb.addRecord(earth), {
           fullResponse: true
         });
 
@@ -1522,7 +1520,7 @@ module('LocalStorageCache - update', function (hooks) {
           'addRecord full response is correct'
         );
 
-        result = cache.update([tb.updateRecord(jupiter)], {
+        result = cache.update(tb.updateRecord(jupiter), {
           fullResponse: true
         });
 
@@ -1607,7 +1605,7 @@ module('LocalStorageCache - update', function (hooks) {
         const tb = cache.transformBuilder;
 
         let result = cache.update(
-          (t) => [t.addRecord({ id: '1', type: 'planet' })],
+          (t) => t.addRecord({ id: '1', type: 'planet' }),
           { fullResponse: true }
         );
 
@@ -1644,15 +1642,14 @@ module('LocalStorageCache - update', function (hooks) {
         );
 
         result = cache.update(
-          (t) => [
+          (t) =>
             t.updateRecord({
               id: '1',
               type: 'planet',
               relationships: {
                 moons: { data: [] }
               }
-            })
-          ],
+            }),
           { fullResponse: true }
         );
 
diff --git a/packages/@orbit/local-storage/test/local-storage-source-pullable-test.ts b/packages/@orbit/local-storage/test/local-storage-source-pullable-test.ts
index f13c8554c..39186a117 100644
--- a/packages/@orbit/local-storage/test/local-storage-source-pullable-test.ts
+++ b/packages/@orbit/local-storage/test/local-storage-source-pullable-test.ts
@@ -3,6 +3,7 @@ import {
   AddRecordOperation,
   InitializedRecord,
   RecordKeyMap,
+  RecordOperation,
   RecordSchema,
   RecordTransform
 } from '@orbit/records';
@@ -112,8 +113,9 @@ module('LocalStorageSource - pullable', function (hooks) {
       source.transformLog.contains(transforms[0].id),
       'log contains transform'
     );
+
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord', 'updateRecord', 'updateRecord'],
       'operations match expectations'
     );
@@ -185,7 +187,7 @@ module('LocalStorageSource - pullable', function (hooks) {
       'log contains transform'
     );
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord', 'updateRecord'],
       'operations match expectations'
     );
@@ -236,12 +238,12 @@ module('LocalStorageSource - pullable', function (hooks) {
       'log contains transform'
     );
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
+      (transforms[0].operations as RecordOperation[]).map((o) => o.op),
       ['updateRecord', 'updateRecord'],
       'operations match expectations'
     );
     assert.deepEqual(
-      transforms[0].operations.map(
+      (transforms[0].operations as RecordOperation[]).map(
         (o) => (o as AddRecordOperation)?.record?.type
       ),
       ['planet', 'moon'],
@@ -302,8 +304,8 @@ module('LocalStorageSource - pullable', function (hooks) {
       'log contains transform'
     );
     assert.deepEqual(
-      transforms[0].operations.map((o) => o.op),
-      ['updateRecord'],
+      (transforms[0].operations as RecordOperation[])[0].op,
+      'updateRecord',
       'operations match expectations'
     );
     assert.equal(
@@ -329,6 +331,10 @@ module('LocalStorageSource - pullable', function (hooks) {
       source.transformLog.contains(transforms[0].id),
       'log contains transform'
     );
-    assert.equal(transforms[0].operations.length, 0, 'no operations returned');
+    assert.equal(
+      (transforms[0].operations as RecordOperation[]).length,
+      0,
+      'no operations returned'
+    );
   });
 });
diff --git a/packages/@orbit/local-storage/test/local-storage-source-queryable-test.ts b/packages/@orbit/local-storage/test/local-storage-source-queryable-test.ts
index a9eecceb7..54b7e8dec 100644
--- a/packages/@orbit/local-storage/test/local-storage-source-queryable-test.ts
+++ b/packages/@orbit/local-storage/test/local-storage-source-queryable-test.ts
@@ -3,6 +3,7 @@ import {
   InitializedRecord,
   RecordKeyMap,
   RecordQuery,
+  RecordQueryExpression,
   RecordSchema
 } from '@orbit/records';
 import { LocalStorageSource } from '../src/local-storage-source';
@@ -84,7 +85,7 @@ module('LocalStorageSource - queryable', function (hooks) {
       attributes: { name: 'Jupiter', classification: 'gas giant' }
     };
 
-    source.cache.patch((t) => t.addRecord(jupiter));
+    source.cache.update((t) => t.addRecord(jupiter));
 
     assert.equal(
       source.cache.getRecordsSync('planet').length,
@@ -111,12 +112,10 @@ module('LocalStorageSource - queryable', function (hooks) {
     };
 
     source.on('beforeQuery', (query: RecordQuery, hints: any) => {
-      if (query.expressions[0].op === 'findRecord') {
-        hints.data = jupiter2;
-      }
+      hints.data = jupiter2;
     });
 
-    source.cache.patch((t) => t.addRecord(jupiter2));
+    source.cache.update((t) => t.addRecord(jupiter2));
 
     assert.equal(
       source.cache.getRecordsSync('planet').length,
@@ -155,10 +154,7 @@ module('LocalStorageSource - queryable', function (hooks) {
     };
 
     source.on('beforeQuery', (query: RecordQuery, hints: any) => {
-      if (
-        query.expressions[0].op === 'findRecords' &&
-        query.options?.sources?.remote.customFilter === 'distantPlanets'
-      ) {
+      if (query.options?.sources?.remote.customFilter === 'distantPlanets') {
         hints.data = [
           { type: 'planet', id: 'uranus' },
           { type: 'planet', id: 'jupiter' }
@@ -166,7 +162,7 @@ module('LocalStorageSource - queryable', function (hooks) {
       }
     });
 
-    source.cache.patch((t) => [
+    source.cache.update((t) => [
       t.addRecord(jupiter),
       t.addRecord(earth),
       t.addRecord(uranus)
diff --git a/packages/@orbit/local-storage/test/local-storage-source-updatable-test.ts b/packages/@orbit/local-storage/test/local-storage-source-updatable-test.ts
index 82aaa6146..d17619c0c 100644
--- a/packages/@orbit/local-storage/test/local-storage-source-updatable-test.ts
+++ b/packages/@orbit/local-storage/test/local-storage-source-updatable-test.ts
@@ -248,7 +248,7 @@ module('LocalStorageSource - updatable', function (hooks) {
       attributes: { name: 'Earth' }
     };
 
-    source.cache.patch((t) => t.addRecord(earth));
+    source.cache.update((t) => t.addRecord(earth));
 
     source.on('beforeUpdate', (transform: RecordTransform, hints: any) => {
       if (transform?.options?.customizeResults) {
diff --git a/packages/@orbit/memory/src/memory-source.ts b/packages/@orbit/memory/src/memory-source.ts
index 51495be24..d0689df89 100644
--- a/packages/@orbit/memory/src/memory-source.ts
+++ b/packages/@orbit/memory/src/memory-source.ts
@@ -28,14 +28,14 @@ import {
   RecordTransformResult,
   RecordUpdatable
 } from '@orbit/records';
-import { Dict } from '@orbit/utils';
+import { Dict, toArray } from '@orbit/utils';
 import {
   MemoryCache,
   MemoryCacheClass,
   MemoryCacheSettings
 } from './memory-cache';
 
-const { deprecate } = Orbit;
+const { assert, deprecate } = Orbit;
 
 export interface MemorySourceSettings<
   QO extends RequestOptions = RecordSourceQueryOptions,
@@ -189,7 +189,12 @@ export class MemorySource<
     }
 
     if (hints?.data) {
-      if (transform.operations.length > 1 && Array.isArray(hints.data)) {
+      if (Array.isArray(transform.operations)) {
+        assert(
+          'MemorySource#update: `hints.data` must be an array if `transform.operations` is an array',
+          Array.isArray(hints.data)
+        );
+
         response.data = (hints.data as RecordOperationResult[]).map((h) =>
           this._retrieveOperationResult(h)
         );
@@ -199,11 +204,7 @@ export class MemorySource<
         );
       }
     } else if (results) {
-      if (transform.operations.length === 1 && Array.isArray(results)) {
-        response.data = results[0];
-      } else {
-        response.data = results;
-      }
+      response.data = results;
     }
 
     if (hints?.details) {
@@ -225,7 +226,12 @@ export class MemorySource<
 
     if (hints?.data) {
       response = {};
-      if (query.expressions.length > 1 && Array.isArray(hints.data)) {
+      if (Array.isArray(query.expressions)) {
+        assert(
+          'MemorySource#query: `hints.data` must be an array if `query.expressions` is an array',
+          Array.isArray(hints.data)
+        );
+
         response.data = (hints.data as RecordQueryExpressionResult[]).map((h) =>
           this._retrieveQueryExpressionResult(h)
         );
@@ -330,7 +336,7 @@ export class MemorySource<
 
     let ops: RecordOperation[] = [];
     transforms.forEach((t) => {
-      Array.prototype.push.apply(ops, t.operations);
+      Array.prototype.push.apply(ops, toArray(t.operations));
     });
 
     if (coalesce !== false) {
diff --git a/packages/@orbit/memory/test/memory-cache-test.ts b/packages/@orbit/memory/test/memory-cache-test.ts
index d2fdd5481..0df3a0415 100644
--- a/packages/@orbit/memory/test/memory-cache-test.ts
+++ b/packages/@orbit/memory/test/memory-cache-test.ts
@@ -975,23 +975,22 @@ module('MemoryCache', function (hooks) {
     let cache = new MemoryCache({ schema, keyMap });
     const tb = cache.transformBuilder;
 
-    cache.update((t) => [
+    cache.update((t) =>
       t.addRecord({
         type: 'planet',
         id: '1',
         attributes: { name: 'Earth' },
         relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
       })
-    ]);
+    );
 
     let result = cache.update(
-      (t) => [
+      (t) =>
         t.updateRecord({
           type: 'planet',
           id: '1',
           attributes: { classification: 'terrestrial' }
-        })
-      ],
+        }),
       { fullResponse: true }
     );
 
@@ -1066,21 +1065,20 @@ module('MemoryCache', function (hooks) {
     let cache = new MemoryCache({ schema, keyMap });
     const tb = cache.transformBuilder;
 
-    cache.update((t) => [
+    cache.update((t) =>
       t.addRecord({
         type: 'planet',
         id: '1',
         attributes: { name: 'Earth' },
         relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
       })
-    ]);
+    );
 
     let result = cache.update(
-      (t) => [
+      (t) =>
         t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
           { type: 'moon', id: 'm1' }
-        ])
-      ],
+        ]),
       { fullResponse: true }
     );
 
@@ -1098,11 +1096,10 @@ module('MemoryCache', function (hooks) {
     );
 
     result = cache.update(
-      (t) => [
+      (t) =>
         t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
           { type: 'moon', id: 'm2' }
-        ])
-      ],
+        ]),
       { fullResponse: true }
     );
 
@@ -1209,7 +1206,7 @@ module('MemoryCache', function (hooks) {
       relationships: { moons: { data: [{ type: 'moon', id: 'm2' }] } }
     };
 
-    let result = cache.update([tb.addRecord(earth)], { fullResponse: true });
+    let result = cache.update(tb.addRecord(earth), { fullResponse: true });
 
     assert.deepEqual(result, {
       data: earth,
@@ -1259,7 +1256,7 @@ module('MemoryCache', function (hooks) {
       }
     });
 
-    result = cache.update([tb.updateRecord(jupiter)], { fullResponse: true });
+    result = cache.update(tb.updateRecord(jupiter), { fullResponse: true });
 
     assert.deepEqual(result, {
       data: jupiter,
diff --git a/packages/@orbit/memory/test/memory-cache-update-test.ts b/packages/@orbit/memory/test/memory-cache-update-test.ts
index a12e142a5..44b39daac 100644
--- a/packages/@orbit/memory/test/memory-cache-update-test.ts
+++ b/packages/@orbit/memory/test/memory-cache-update-test.ts
@@ -1222,23 +1222,22 @@ module('MemoryCache - update', function (hooks) {
         const cache = new MemoryCache({ schema, keyMap });
         const tb = cache.transformBuilder;
 
-        cache.update((t) => [
+        cache.update((t) =>
           t.addRecord({
             type: 'planet',
             id: '1',
             attributes: { name: 'Earth' },
             relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
           })
-        ]);
+        );
 
         let result = cache.update(
-          (t) => [
+          (t) =>
             t.updateRecord({
               type: 'planet',
               id: '1',
               attributes: { classification: 'terrestrial' }
-            })
-          ],
+            }),
           { fullResponse: true }
         );
 
@@ -1313,21 +1312,20 @@ module('MemoryCache - update', function (hooks) {
         const cache = new MemoryCache({ schema, keyMap });
         const tb = cache.transformBuilder;
 
-        cache.update((t) => [
+        cache.update((t) =>
           t.addRecord({
             type: 'planet',
             id: '1',
             attributes: { name: 'Earth' },
             relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
           })
-        ]);
+        );
 
         let result = cache.update(
-          (t) => [
+          (t) =>
             t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
               { type: 'moon', id: 'm1' }
-            ])
-          ],
+            ]),
           { fullResponse: true }
         );
 
@@ -1463,7 +1461,7 @@ module('MemoryCache - update', function (hooks) {
           relationships: { moons: { data: [{ type: 'moon', id: 'm2' }] } }
         };
 
-        let result = cache.update([tb.addRecord(earth)], {
+        let result = cache.update(tb.addRecord(earth), {
           fullResponse: true
         });
 
@@ -1518,7 +1516,7 @@ module('MemoryCache - update', function (hooks) {
           'addRecord full response is correct'
         );
 
-        result = cache.update([tb.updateRecord(jupiter)], {
+        result = cache.update(tb.updateRecord(jupiter), {
           fullResponse: true
         });
 
@@ -1603,7 +1601,7 @@ module('MemoryCache - update', function (hooks) {
         const tb = cache.transformBuilder;
 
         let result = cache.update(
-          (t) => [t.addRecord({ id: '1', type: 'planet' })],
+          (t) => t.addRecord({ id: '1', type: 'planet' }),
           { fullResponse: true }
         );
 
@@ -1640,15 +1638,14 @@ module('MemoryCache - update', function (hooks) {
         );
 
         result = cache.update(
-          (t) => [
+          (t) =>
             t.updateRecord({
               id: '1',
               type: 'planet',
               relationships: {
                 moons: { data: [] }
               }
-            })
-          ],
+            }),
           { fullResponse: true }
         );
 
diff --git a/packages/@orbit/memory/test/memory-source-queryable-test.ts b/packages/@orbit/memory/test/memory-source-queryable-test.ts
index ad1998faa..e199797bf 100644
--- a/packages/@orbit/memory/test/memory-source-queryable-test.ts
+++ b/packages/@orbit/memory/test/memory-source-queryable-test.ts
@@ -105,9 +105,7 @@ module('MemorySource - queryable', function (hooks) {
     };
 
     source.on('beforeQuery', (query: RecordQuery, hints: any) => {
-      if (query.expressions[0].op === 'findRecord') {
-        hints.data = jupiter2;
-      }
+      hints.data = jupiter2;
     });
 
     source.cache.patch((t) => t.addRecord(jupiter2));
@@ -149,10 +147,7 @@ module('MemorySource - queryable', function (hooks) {
     };
 
     source.on('beforeQuery', (query: RecordQuery, hints: any) => {
-      if (
-        query.expressions[0].op === 'findRecords' &&
-        query.options?.sources?.remote.customFilter === 'distantPlanets'
-      ) {
+      if (query.options?.sources?.remote.customFilter === 'distantPlanets') {
         hints.data = [
           { type: 'planet', id: 'uranus' },
           { type: 'planet', id: 'jupiter' }
diff --git a/packages/@orbit/record-cache/src/async-record-cache.ts b/packages/@orbit/record-cache/src/async-record-cache.ts
index 66dbd2386..b4e06f7e8 100644
--- a/packages/@orbit/record-cache/src/async-record-cache.ts
+++ b/packages/@orbit/record-cache/src/async-record-cache.ts
@@ -21,7 +21,6 @@ import {
   RecordQuery,
   RecordQueryBuilder,
   RecordQueryExpression,
-  RecordQueryExpressionResult,
   RecordQueryResult,
   recordsReferencedByOperations,
   RecordTransform,
@@ -29,7 +28,7 @@ import {
   RecordTransformBuilderFunc,
   RecordTransformResult
 } from '@orbit/records';
-import { deepGet, Dict } from '@orbit/utils';
+import { deepGet, Dict, toArray } from '@orbit/utils';
 import {
   AsyncOperationProcessor,
   AsyncOperationProcessorClass
@@ -375,24 +374,36 @@ export abstract class AsyncRecordCache<
     // eslint-disable-next-line @typescript-eslint/no-unused-vars
     options?: QO
   ): Promise<FullResponse<RequestData, QueryResponseDetails, RecordOperation>> {
-    const results: RecordQueryExpressionResult[] = [];
-
-    for (let expression of query.expressions) {
+    let data;
+
+    if (Array.isArray(query.expressions)) {
+      data = [];
+      for (let expression of query.expressions) {
+        const queryOperator = this.getQueryOperator(expression.op);
+        if (!queryOperator) {
+          throw new Error(`Unable to find query operator: ${expression.op}`);
+        }
+        data.push(
+          await queryOperator(
+            this,
+            expression,
+            this.getQueryOptions(query, expression)
+          )
+        );
+      }
+    } else {
+      const expression = query.expressions as RecordQueryExpression;
       const queryOperator = this.getQueryOperator(expression.op);
       if (!queryOperator) {
         throw new Error(`Unable to find query operator: ${expression.op}`);
       }
-      results.push(
-        await queryOperator(
-          this,
-          expression,
-          this.getQueryOptions(query, expression)
-        )
+      data = await queryOperator(
+        this,
+        expression,
+        this.getQueryOptions(query, expression)
       );
     }
 
-    const data = query.expressions.length === 1 ? results[0] : results;
-
     return { data: data as RequestData };
   }
 
@@ -448,17 +459,26 @@ export abstract class AsyncRecordCache<
         };
       }
 
-      await this._applyTransformOperations(
-        transform,
-        transform.operations,
-        response,
-        true
-      );
       let data: RecordTransformResult;
-      if (transform.operations.length === 1 && Array.isArray(response.data)) {
-        data = response.data[0];
-      } else {
+
+      if (Array.isArray(transform.operations)) {
+        await this._applyTransformOperations(
+          transform,
+          transform.operations,
+          response,
+          true
+        );
         data = response.data;
+      } else {
+        await this._applyTransformOperation(
+          transform,
+          transform.operations,
+          response,
+          true
+        );
+        if (Array.isArray(response.data)) {
+          data = response.data[0];
+        }
       }
 
       if (options?.fullResponse) {
@@ -491,7 +511,9 @@ export abstract class AsyncRecordCache<
   ): Promise<RecordTransformBuffer> {
     const buffer = this._getTransformBuffer();
 
-    const records = recordsReferencedByOperations(transform.operations);
+    const records = recordsReferencedByOperations(
+      toArray(transform.operations)
+    );
     const inverseRelationships = await this.getInverseRelationshipsAsync(
       records
     );
diff --git a/packages/@orbit/record-cache/src/live-query/live-query.ts b/packages/@orbit/record-cache/src/live-query/live-query.ts
index 4d10c48da..285be19c4 100644
--- a/packages/@orbit/record-cache/src/live-query/live-query.ts
+++ b/packages/@orbit/record-cache/src/live-query/live-query.ts
@@ -54,7 +54,7 @@ export abstract class LiveQuery {
   constructor(settings: LiveQuerySettings) {
     assert(
       'Only single expression queries are supported on LiveQuery',
-      settings.query.expressions.length === 1
+      !Array.isArray(settings.query.expressions)
     );
     this.debounce = settings.debounce;
     this._query = settings.query;
@@ -62,7 +62,7 @@ export abstract class LiveQuery {
 
   operationRelevantForQuery(operation: RecordOperation): boolean {
     const change = recordOperationChange(operation);
-    const expression = this._query.expressions[0];
+    const expression = this._query.expressions as RecordQueryExpression;
     return this.queryExpressionRelevantForChange(expression, change);
   }
 
diff --git a/packages/@orbit/record-cache/src/sync-record-cache.ts b/packages/@orbit/record-cache/src/sync-record-cache.ts
index c0a54df3f..6b3d2efa6 100644
--- a/packages/@orbit/record-cache/src/sync-record-cache.ts
+++ b/packages/@orbit/record-cache/src/sync-record-cache.ts
@@ -19,7 +19,6 @@ import {
   RecordQuery,
   RecordQueryBuilder,
   RecordQueryExpression,
-  RecordQueryExpressionResult,
   RecordQueryResult,
   recordsReferencedByOperations,
   RecordTransform,
@@ -29,7 +28,7 @@ import {
   SyncRecordQueryable,
   SyncRecordUpdatable
 } from '@orbit/records';
-import { deepGet, Dict } from '@orbit/utils';
+import { deepGet, Dict, toArray } from '@orbit/utils';
 import { SyncLiveQuery } from './live-query/sync-live-query';
 import { SyncCacheIntegrityProcessor } from './operation-processors/sync-cache-integrity-processor';
 import { SyncSchemaConsistencyProcessor } from './operation-processors/sync-schema-consistency-processor';
@@ -355,20 +354,36 @@ export abstract class SyncRecordCache<
     // eslint-disable-next-line @typescript-eslint/no-unused-vars
     options?: QO
   ): FullResponse<RequestData, QueryResponseDetails, RecordOperation> {
-    const results: RecordQueryExpressionResult[] = [];
-
-    for (let expression of query.expressions) {
+    let data;
+
+    if (Array.isArray(query.expressions)) {
+      data = [];
+      for (let expression of query.expressions) {
+        const queryOperator = this.getQueryOperator(expression.op);
+        if (!queryOperator) {
+          throw new Error(`Unable to find query operator: ${expression.op}`);
+        }
+        data.push(
+          queryOperator(
+            this,
+            expression,
+            this.getQueryOptions(query, expression)
+          )
+        );
+      }
+    } else {
+      const expression = query.expressions as RecordQueryExpression;
       const queryOperator = this.getQueryOperator(expression.op);
       if (!queryOperator) {
         throw new Error(`Unable to find query operator: ${expression.op}`);
       }
-      results.push(
-        queryOperator(this, expression, this.getQueryOptions(query, expression))
+      data = queryOperator(
+        this,
+        expression,
+        this.getQueryOptions(query, expression)
       );
     }
 
-    const data = query.expressions.length === 1 ? results[0] : results;
-
     return { data: data as RequestData };
   }
 
@@ -422,18 +437,26 @@ export abstract class SyncRecordCache<
         };
       }
 
-      this._applyTransformOperations(
-        transform,
-        transform.operations,
-        response,
-        true
-      );
-
       let data: RecordTransformResult;
-      if (transform.operations.length === 1 && Array.isArray(response.data)) {
-        data = response.data[0];
-      } else {
+
+      if (Array.isArray(transform.operations)) {
+        this._applyTransformOperations(
+          transform,
+          transform.operations,
+          response,
+          true
+        );
         data = response.data;
+      } else {
+        this._applyTransformOperation(
+          transform,
+          transform.operations,
+          response,
+          true
+        );
+        if (Array.isArray(response.data)) {
+          data = response.data[0];
+        }
       }
 
       if (options?.fullResponse) {
@@ -466,7 +489,9 @@ export abstract class SyncRecordCache<
   ): RecordTransformBuffer {
     const buffer = this._getTransformBuffer();
 
-    const records = recordsReferencedByOperations(transform.operations);
+    const records = recordsReferencedByOperations(
+      toArray(transform.operations)
+    );
     const inverseRelationships = this.getInverseRelationshipsSync(records);
     const relatedRecords = inverseRelationships.map((ir) => ir.record);
     Array.prototype.push.apply(records, relatedRecords);
diff --git a/packages/@orbit/record-cache/test/async-record-cache-query-test.ts b/packages/@orbit/record-cache/test/async-record-cache-query-test.ts
index d5ff032fd..e07171e47 100644
--- a/packages/@orbit/record-cache/test/async-record-cache-query-test.ts
+++ b/packages/@orbit/record-cache/test/async-record-cache-query-test.ts
@@ -31,16 +31,16 @@ module('AsyncRecordCache - query', function (hooks) {
       }
     };
 
-    const updatedRecord = await cache.update<InitializedRecord>((t) => [
+    const updatedRecord = await cache.update<InitializedRecord>((t) =>
       t.addRecord(jupiter)
-    ]);
+    );
 
     const foundRecord = await cache.query<InitializedRecord>((q) =>
       q.findRecord({ type: 'planet', id: 'jupiter' })
     );
 
-    assert.strictEqual(updatedRecord, jupiter);
-    assert.strictEqual(foundRecord, jupiter);
+    assert.strictEqual(updatedRecord, jupiter, 'updated record is correct');
+    assert.strictEqual(foundRecord, jupiter, 'found record is correct');
   });
 
   test('#query can retrieve multiple expressions', async function (assert) {
diff --git a/packages/@orbit/record-cache/test/async-record-cache-update-test.ts b/packages/@orbit/record-cache/test/async-record-cache-update-test.ts
index da217b478..fe7bc9d00 100644
--- a/packages/@orbit/record-cache/test/async-record-cache-update-test.ts
+++ b/packages/@orbit/record-cache/test/async-record-cache-update-test.ts
@@ -975,23 +975,22 @@ module('AsyncRecordCache - update', function (hooks) {
         test('#update merges records when "replacing" and will not stomp on attributes and relationships that are not replaced', async function (assert) {
           const tb = cache.transformBuilder;
 
-          await cache.update((t) => [
+          await cache.update((t) =>
             t.addRecord({
               type: 'planet',
               id: '1',
               attributes: { name: 'Earth' },
               relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
             })
-          ]);
+          );
 
           let result = await cache.update(
-            (t) => [
+            (t) =>
               t.updateRecord({
                 type: 'planet',
                 id: '1',
                 attributes: { classification: 'terrestrial' }
-              })
-            ],
+              }),
             { fullResponse: true }
           );
 
@@ -1065,21 +1064,20 @@ module('AsyncRecordCache - update', function (hooks) {
         test('#update can replace related records but only if they are different', async function (assert) {
           const tb = cache.transformBuilder;
 
-          await cache.update((t) => [
+          await cache.update((t) =>
             t.addRecord({
               type: 'planet',
               id: '1',
               attributes: { name: 'Earth' },
               relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
             })
-          ]);
+          );
 
           let result = await cache.update(
-            (t) => [
+            (t) =>
               t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
                 { type: 'moon', id: 'm1' }
-              ])
-            ],
+              ]),
             { fullResponse: true }
           );
 
@@ -1226,7 +1224,7 @@ module('AsyncRecordCache - update', function (hooks) {
             relationships: { moons: { data: [{ type: 'moon', id: 'm2' }] } }
           };
 
-          let result = await cache.update([tb.addRecord(earth)], {
+          let result = await cache.update(tb.addRecord(earth), {
             fullResponse: true
           });
 
@@ -1285,7 +1283,7 @@ module('AsyncRecordCache - update', function (hooks) {
             'addRecord full response is correct'
           );
 
-          result = await cache.update([tb.updateRecord(jupiter)], {
+          result = await cache.update(tb.updateRecord(jupiter), {
             fullResponse: true
           });
 
@@ -1369,7 +1367,7 @@ module('AsyncRecordCache - update', function (hooks) {
           const tb = cache.transformBuilder;
 
           let result = await cache.update(
-            (t) => [t.addRecord({ id: '1', type: 'planet' })],
+            (t) => t.addRecord({ id: '1', type: 'planet' }),
             { fullResponse: true }
           );
 
@@ -1406,15 +1404,14 @@ module('AsyncRecordCache - update', function (hooks) {
           );
 
           result = await cache.update(
-            (t) => [
+            (t) =>
               t.updateRecord({
                 id: '1',
                 type: 'planet',
                 relationships: {
                   moons: { data: [] }
                 }
-              })
-            ],
+              }),
             { fullResponse: true }
           );
 
diff --git a/packages/@orbit/record-cache/test/sync-record-cache-query-test.ts b/packages/@orbit/record-cache/test/sync-record-cache-query-test.ts
index 15186c6fb..7e888e29d 100644
--- a/packages/@orbit/record-cache/test/sync-record-cache-query-test.ts
+++ b/packages/@orbit/record-cache/test/sync-record-cache-query-test.ts
@@ -31,16 +31,16 @@ module('SyncRecordCache - query', function (hooks) {
       }
     };
 
-    const updatedRecord = cache.update<InitializedRecord>((t) => [
+    const updatedRecord = cache.update<InitializedRecord>((t) =>
       t.addRecord(jupiter)
-    ]);
+    );
 
     const foundRecord = cache.query<InitializedRecord>((q) =>
       q.findRecord({ type: 'planet', id: 'jupiter' })
     );
 
-    assert.strictEqual(updatedRecord, jupiter);
-    assert.strictEqual(foundRecord, jupiter);
+    assert.strictEqual(updatedRecord, jupiter, 'updated record is correct');
+    assert.strictEqual(foundRecord, jupiter, 'found record is correct');
   });
 
   test('#query can retrieve multiple expressions', function (assert) {
diff --git a/packages/@orbit/record-cache/test/sync-record-cache-update-test.ts b/packages/@orbit/record-cache/test/sync-record-cache-update-test.ts
index 86fc2d006..118a971b5 100644
--- a/packages/@orbit/record-cache/test/sync-record-cache-update-test.ts
+++ b/packages/@orbit/record-cache/test/sync-record-cache-update-test.ts
@@ -1222,23 +1222,22 @@ module('SyncRecordCache', function (hooks) {
         const cache = new ExampleSyncRecordCache({ schema, keyMap });
         const tb = cache.transformBuilder;
 
-        cache.update((t) => [
+        cache.update((t) =>
           t.addRecord({
             type: 'planet',
             id: '1',
             attributes: { name: 'Earth' },
             relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
           })
-        ]);
+        );
 
         let result = cache.update(
-          (t) => [
+          (t) =>
             t.updateRecord({
               type: 'planet',
               id: '1',
               attributes: { classification: 'terrestrial' }
-            })
-          ],
+            }),
           { fullResponse: true }
         );
 
@@ -1313,21 +1312,20 @@ module('SyncRecordCache', function (hooks) {
         const cache = new ExampleSyncRecordCache({ schema, keyMap });
         const tb = cache.transformBuilder;
 
-        cache.update((t) => [
+        cache.update((t) =>
           t.addRecord({
             type: 'planet',
             id: '1',
             attributes: { name: 'Earth' },
             relationships: { moons: { data: [{ type: 'moon', id: 'm1' }] } }
           })
-        ]);
+        );
 
         let result = cache.update(
-          (t) => [
+          (t) =>
             t.replaceRelatedRecords({ type: 'planet', id: '1' }, 'moons', [
               { type: 'moon', id: 'm1' }
-            ])
-          ],
+            ]),
           { fullResponse: true }
         );
 
@@ -1463,7 +1461,7 @@ module('SyncRecordCache', function (hooks) {
           relationships: { moons: { data: [{ type: 'moon', id: 'm2' }] } }
         };
 
-        let result = cache.update([tb.addRecord(earth)], {
+        let result = cache.update(tb.addRecord(earth), {
           fullResponse: true
         });
 
@@ -1518,7 +1516,7 @@ module('SyncRecordCache', function (hooks) {
           'addRecord full response is correct'
         );
 
-        result = cache.update([tb.updateRecord(jupiter)], {
+        result = cache.update(tb.updateRecord(jupiter), {
           fullResponse: true
         });
 
@@ -1603,7 +1601,7 @@ module('SyncRecordCache', function (hooks) {
         const tb = cache.transformBuilder;
 
         let result = cache.update(
-          (t) => [t.addRecord({ id: '1', type: 'planet' })],
+          (t) => t.addRecord({ id: '1', type: 'planet' }),
           { fullResponse: true }
         );
 
@@ -1640,15 +1638,14 @@ module('SyncRecordCache', function (hooks) {
         );
 
         result = cache.update(
-          (t) => [
+          (t) =>
             t.updateRecord({
               id: '1',
               type: 'planet',
               relationships: {
                 moons: { data: [] }
               }
-            })
-          ],
+            }),
           { fullResponse: true }
         );
 
diff --git a/packages/@orbit/records/src/record-query.ts b/packages/@orbit/records/src/record-query.ts
index 348d72d92..9df6ea9ae 100644
--- a/packages/@orbit/records/src/record-query.ts
+++ b/packages/@orbit/records/src/record-query.ts
@@ -5,9 +5,7 @@ import {
   RecordQueryExpressionResult
 } from './record-query-expression';
 
-export interface RecordQuery extends Query<RecordQueryExpression> {
-  expressions: RecordQueryExpression[];
-}
+export type RecordQuery = Query<RecordQueryExpression>;
 
 export type RecordQueryResult<T = InitializedRecord> =
   | RecordQueryExpressionResult<T>
diff --git a/packages/@orbit/records/src/record-transform.ts b/packages/@orbit/records/src/record-transform.ts
index 01b1e66ce..92fc5de60 100644
--- a/packages/@orbit/records/src/record-transform.ts
+++ b/packages/@orbit/records/src/record-transform.ts
@@ -2,9 +2,7 @@ import { RecordOperation, RecordOperationResult } from './record-operation';
 import { InitializedRecord } from './record';
 import { Transform } from '@orbit/data';
 
-export interface RecordTransform extends Transform<RecordOperation> {
-  operations: RecordOperation[];
-}
+export type RecordTransform = Transform<RecordOperation>;
 
 export type RecordTransformResult<T = InitializedRecord> =
   | RecordOperationResult<T>