diff --git a/packages/vest/src/core/VestBus/VestBus.ts b/packages/vest/src/core/VestBus/VestBus.ts
index 62ac0bfb0..03b7e7aac 100644
--- a/packages/vest/src/core/VestBus/VestBus.ts
+++ b/packages/vest/src/core/VestBus/VestBus.ts
@@ -12,7 +12,6 @@ import {
 import { TFieldName } from 'SuiteResultTypes';
 import { TestWalker } from 'TestWalker';
 import { VestTest } from 'VestTest';
-import { isIsolateTest } from 'isIsolateTest';
 import { useOmitOptionalFields } from 'omitOptionalFields';
 import { useRunDoneCallbacks, useRunFieldCallbacks } from 'runCallbacks';
 
@@ -42,7 +41,7 @@ export function useInitVestBus() {
   });
 
   on(RuntimeEvents.ISOLATE_PENDING, (isolate: TIsolate) => {
-    if (isIsolateTest(isolate)) {
+    if (VestTest.is(isolate)) {
       VestTest.setPending(isolate);
     }
 
@@ -50,7 +49,7 @@ export function useInitVestBus() {
   });
 
   on(RuntimeEvents.ISOLATE_DONE, (isolate: TIsolate) => {
-    if (isIsolateTest(isolate)) {
+    if (VestTest.is(isolate)) {
       VestBus.emit(Events.TEST_COMPLETED, isolate);
     }
 
diff --git a/packages/vest/src/core/isolate/IsolateTest/IsolateTestReconciler.ts b/packages/vest/src/core/isolate/IsolateTest/IsolateTestReconciler.ts
index d0c510632..355a03639 100644
--- a/packages/vest/src/core/isolate/IsolateTest/IsolateTestReconciler.ts
+++ b/packages/vest/src/core/isolate/IsolateTest/IsolateTestReconciler.ts
@@ -7,13 +7,12 @@ import { IsolateReconciler } from 'IsolateReconciler';
 import type { TIsolateTest } from 'IsolateTest';
 import { VestTest } from 'VestTest';
 import cancelOverriddenPendingTest from 'cancelOverriddenPendingTest';
-import { castIsolateTest, isIsolateTest } from 'isIsolateTest';
 import { isSameProfileTest } from 'isSameProfileTest';
 import { useVerifyTestRun } from 'verifyTestRun';
 
 export class IsolateTestReconciler extends IsolateReconciler {
   static match(currentNode: TIsolate, historyNode: TIsolate): boolean {
-    return isIsolateTest(currentNode) && isIsolateTest(historyNode);
+    return VestTest.is(currentNode) && VestTest.is(historyNode);
   }
 
   static reconcile(
@@ -46,7 +45,7 @@ function handleCollision(
   prevNode?: TIsolate
 ): TIsolateTest {
   if (IsolateInspector.usesKey(newNode)) {
-    return castIsolateTest(Reconciler.handleIsolateNodeWithKey(newNode));
+    return VestTest.cast(Reconciler.handleIsolateNodeWithKey(newNode));
   }
 
   if (
@@ -56,7 +55,7 @@ function handleCollision(
     return newNode;
   }
 
-  if (!isIsolateTest(prevNode)) {
+  if (!VestTest.is(prevNode)) {
     // I believe we cannot actually reach this point.
     // Because it should already be handled by nodeReorderDetected.
     /* istanbul ignore next */
@@ -81,7 +80,7 @@ function cancelOverriddenPendingTestOnTestReRun(
   currentNode: TIsolate,
   prevTestObject: TIsolateTest
 ) {
-  if (nextNode === currentNode && isIsolateTest(currentNode)) {
+  if (nextNode === currentNode && VestTest.is(currentNode)) {
     cancelOverriddenPendingTest(prevTestObject, currentNode);
   }
 }
@@ -90,7 +89,7 @@ function nodeReorderDetected(
   newNode: TIsolateTest,
   prevNode: Maybe<TIsolate>
 ): boolean {
-  return isIsolateTest(prevNode) && !isSameProfileTest(prevNode, newNode);
+  return VestTest.is(prevNode) && !isSameProfileTest(prevNode, newNode);
 }
 
 function throwTestOrderError(
@@ -104,7 +103,7 @@ function throwTestOrderError(
   deferThrow(
     text(ErrorStrings.TESTS_CALLED_IN_DIFFERENT_ORDER, {
       fieldName: VestTest.getData(newNode).fieldName,
-      prevName: isIsolateTest(prevNode)
+      prevName: VestTest.is(prevNode)
         ? VestTest.getData(prevNode).fieldName
         : undefined,
     })
diff --git a/packages/vest/src/core/isolate/IsolateTest/TestWalker.ts b/packages/vest/src/core/isolate/IsolateTest/TestWalker.ts
index e9bad9284..e410d95cb 100644
--- a/packages/vest/src/core/isolate/IsolateTest/TestWalker.ts
+++ b/packages/vest/src/core/isolate/IsolateTest/TestWalker.ts
@@ -4,7 +4,6 @@ import { Walker, VestRuntime, TIsolate } from 'vestjs-runtime';
 import { TIsolateTest } from 'IsolateTest';
 import { TFieldName, TGroupName } from 'SuiteResultTypes';
 import { VestTest } from 'VestTest';
-import { castIsolateTest, isIsolateTest, isIsolateTestX } from 'isIsolateTest';
 import matchingFieldName from 'matchingFieldName';
 
 type MaybeRoot = Nullable<TIsolate>;
@@ -14,7 +13,7 @@ export class TestWalker {
 
   static hasNoTests(root: MaybeRoot = TestWalker.defaultRoot()): boolean {
     if (!root) return true;
-    return !Walker.has(root, isIsolateTest);
+    return !Walker.has(root, VestTest.is);
   }
 
   static someIncompleteTests(
@@ -25,11 +24,11 @@ export class TestWalker {
     return Walker.some(
       root,
       isolate => {
-        isIsolateTestX(isolate);
+        VestTest.isX(isolate);
 
         return VestTest.isPending(isolate) && predicate(isolate);
       },
-      isIsolateTest
+      VestTest.is
     );
   }
 
@@ -41,11 +40,11 @@ export class TestWalker {
     return Walker.some(
       root,
       isolate => {
-        isIsolateTestX(isolate);
+        VestTest.isX(isolate);
 
         return predicate(isolate);
       },
-      isIsolateTest
+      VestTest.is
     );
   }
 
@@ -57,11 +56,11 @@ export class TestWalker {
     return Walker.every(
       root,
       isolate => {
-        isIsolateTestX(isolate);
+        VestTest.isX(isolate);
 
         return predicate(isolate);
       },
-      isIsolateTest
+      VestTest.is
     );
   }
 
@@ -73,9 +72,9 @@ export class TestWalker {
     Walker.walk(
       root,
       (isolate, breakout) => {
-        callback(castIsolateTest(isolate), breakout);
+        callback(VestTest.cast<F, G>(isolate), breakout);
       },
-      isIsolateTest
+      VestTest.is
     );
   }
 
@@ -96,11 +95,11 @@ export class TestWalker {
     Walker.pluck(
       root,
       isolate => {
-        isIsolateTestX(isolate);
+        VestTest.isX(isolate);
 
         return predicate(isolate);
       },
-      isIsolateTest
+      VestTest.is
     );
   }
 
diff --git a/packages/vest/src/core/isolate/IsolateTest/VestTest.ts b/packages/vest/src/core/isolate/IsolateTest/VestTest.ts
index 61f5f61a1..d3057b928 100644
--- a/packages/vest/src/core/isolate/IsolateTest/VestTest.ts
+++ b/packages/vest/src/core/isolate/IsolateTest/VestTest.ts
@@ -1,5 +1,7 @@
-import { invariant, isPromise, optionalFunctionValue } from 'vest-utils';
+import { Maybe, invariant, isPromise, optionalFunctionValue } from 'vest-utils';
+import { IsolateSelectors, TIsolate } from 'vestjs-runtime';
 
+import { ErrorStrings } from 'ErrorStrings';
 import type { TIsolateTest } from 'IsolateTest';
 import {
   IsolateTestStateMachine,
@@ -9,6 +11,7 @@ import {
 } from 'IsolateTestStateMachine';
 import { TestSeverity } from 'Severity';
 import { TFieldName, TGroupName } from 'SuiteResultTypes';
+import { VestIsolateType } from 'VestIsolateType';
 
 export class VestTest {
   // Read
@@ -21,6 +24,24 @@ export class VestTest {
     return test.data;
   }
 
+  static is(isolate?: Maybe<TIsolate>): isolate is TIsolateTest {
+    return IsolateSelectors.isIsolateType<TIsolateTest>(
+      isolate,
+      VestIsolateType.Test
+    );
+  }
+
+  static isX(isolate?: Maybe<TIsolate>): asserts isolate is TIsolateTest {
+    invariant(VestTest.is(isolate), ErrorStrings.EXPECTED_VEST_TEST);
+  }
+
+  static cast<F extends TFieldName = string, G extends TGroupName = string>(
+    isolate?: Maybe<TIsolate>
+  ): TIsolateTest<F, G> {
+    VestTest.isX(isolate);
+    return isolate as TIsolateTest<F, G>;
+  }
+
   static warns(test: TIsolateTest): boolean {
     return VestTest.getData(test).severity === TestSeverity.Warning;
   }
diff --git a/packages/vest/src/core/isolate/IsolateTest/isIsolateTest.ts b/packages/vest/src/core/isolate/IsolateTest/isIsolateTest.ts
deleted file mode 100644
index 33aae087b..000000000
--- a/packages/vest/src/core/isolate/IsolateTest/isIsolateTest.ts
+++ /dev/null
@@ -1,30 +0,0 @@
-import { Maybe, invariant } from 'vest-utils';
-import { TIsolate, IsolateSelectors } from 'vestjs-runtime';
-
-import type { TIsolateTest } from 'IsolateTest';
-import { TFieldName, TGroupName } from 'SuiteResultTypes';
-import { VestIsolateType } from 'VestIsolateType';
-
-export function isIsolateTest(
-  isolate?: Maybe<TIsolate>
-): isolate is TIsolateTest {
-  return IsolateSelectors.isIsolateType<TIsolateTest>(
-    isolate,
-    VestIsolateType.Test
-  );
-}
-
-export function isIsolateTestX(
-  isolate: TIsolate
-): asserts isolate is TIsolateTest {
-  invariant(isIsolateTest(isolate));
-}
-
-export function castIsolateTest<
-  F extends TFieldName = TFieldName,
-  G extends TGroupName = TGroupName
->(isolate: TIsolate): TIsolateTest<F, G> {
-  isIsolateTestX(isolate);
-
-  return isolate as TIsolateTest<F, G>;
-}
diff --git a/packages/vest/src/core/test/__tests__/runAsyncTest.test.ts b/packages/vest/src/core/test/__tests__/runAsyncTest.test.ts
index 59705a8c1..575ee890e 100644
--- a/packages/vest/src/core/test/__tests__/runAsyncTest.test.ts
+++ b/packages/vest/src/core/test/__tests__/runAsyncTest.test.ts
@@ -1,7 +1,5 @@
 import wait from 'wait';
 
-import { asVestTest } from '../../../testUtils/asVestTest';
-
 import { TIsolateTest } from 'IsolateTest';
 import { VestTest } from 'VestTest';
 import * as vest from 'vest';
@@ -17,7 +15,7 @@ describe('runAsyncTest', () => {
       });
       suite();
 
-      testObject = asVestTest(testObject);
+      testObject = VestTest.cast(testObject);
 
       expect(VestTest.isPending(testObject)).toBe(true);
       await wait(100);
@@ -132,7 +130,7 @@ describe('runAsyncTest', () => {
         });
         suite();
 
-        testObject = asVestTest(testObject);
+        testObject = VestTest.cast(testObject);
 
         expect(VestTest.isPassing(testObject)).toBe(false);
         await wait(100);
@@ -149,7 +147,7 @@ describe('runAsyncTest', () => {
         });
         suite();
 
-        testObject = asVestTest(testObject);
+        testObject = VestTest.cast(testObject);
 
         expect(VestTest.isFailing(testObject)).toBe(false);
         await wait(100);
@@ -167,7 +165,7 @@ describe('runAsyncTest', () => {
         });
         suite();
 
-        testObject = asVestTest(testObject);
+        testObject = VestTest.cast(testObject);
 
         expect(VestTest.isWarning(testObject)).toBe(false);
         await wait(100);
diff --git a/packages/vest/src/hooks/__tests__/warn.test.ts b/packages/vest/src/hooks/__tests__/warn.test.ts
index 5bac845c6..523b08ed8 100644
--- a/packages/vest/src/hooks/__tests__/warn.test.ts
+++ b/packages/vest/src/hooks/__tests__/warn.test.ts
@@ -1,9 +1,7 @@
 import { faker } from '@faker-js/faker';
-import { VestTest } from 'VestTest';
-
-import { asVestTest } from '../../testUtils/asVestTest';
 
 import { ErrorStrings } from 'ErrorStrings';
+import { VestTest } from 'VestTest';
 import * as vest from 'vest';
 
 const { create, test, warn } = vest;
@@ -18,7 +16,7 @@ describe('warn hook', () => {
         });
       })();
 
-      expect(VestTest.warns(asVestTest(t))).toBe(true);
+      expect(VestTest.warns(VestTest.cast(t))).toBe(true);
     });
   });
 
diff --git a/packages/vest/src/testUtils/asVestTest.ts b/packages/vest/src/testUtils/asVestTest.ts
deleted file mode 100644
index 46053a332..000000000
--- a/packages/vest/src/testUtils/asVestTest.ts
+++ /dev/null
@@ -1,10 +0,0 @@
-import { invariant } from 'vest-utils';
-
-import { ErrorStrings } from 'ErrorStrings';
-import { TIsolateTest } from 'IsolateTest';
-import { isIsolateTest } from 'isIsolateTest';
-
-export function asVestTest(value: any): TIsolateTest {
-  invariant(isIsolateTest(value), ErrorStrings.EXPECTED_VEST_TEST);
-  return value;
-}
diff --git a/packages/vest/tsconfig.json b/packages/vest/tsconfig.json
index 3b4038049..b57f400af 100644
--- a/packages/vest/tsconfig.json
+++ b/packages/vest/tsconfig.json
@@ -14,7 +14,6 @@
       "suiteDummy": ["./src/testUtils/suiteDummy.ts"],
       "partition": ["./src/testUtils/partition.ts"],
       "mockThrowError": ["./src/testUtils/mockThrowError.ts"],
-      "asVestTest": ["./src/testUtils/asVestTest.ts"],
       "TVestMock": ["./src/testUtils/TVestMock.ts"],
       "suiteRunResult": ["./src/suiteResult/suiteRunResult.ts"],
       "suiteResult": ["./src/suiteResult/suiteResult.ts"],
@@ -92,7 +91,6 @@
       "isSameProfileTest": [
         "./src/core/isolate/IsolateTest/isSameProfileTest.ts"
       ],
-      "isIsolateTest": ["./src/core/isolate/IsolateTest/isIsolateTest.ts"],
       "cancelOverriddenPendingTest": [
         "./src/core/isolate/IsolateTest/cancelOverriddenPendingTest.ts"
       ],