diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3ba4f4faea..d9cd933db8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,7 +2,7 @@
 # For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-maven
 name: continuous-integration
 env:
-  USE_BAZEL_VERSION: '4.2.2'
+  USE_BAZEL_VERSION: '6.1.2'
   USE_JAVA_DISTRIBUTION: 'zulu'
   USE_JAVA_VERSION: '11'
 
diff --git a/core/src/com/google/inject/internal/aop/AnonymousClassDefiner.java b/core/src/com/google/inject/internal/aop/AnonymousClassDefiner.java
index 87c47a6ba6..e26d20ea41 100644
--- a/core/src/com/google/inject/internal/aop/AnonymousClassDefiner.java
+++ b/core/src/com/google/inject/internal/aop/AnonymousClassDefiner.java
@@ -16,7 +16,6 @@
 
 package com.google.inject.internal.aop;
 
-import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 
 /**
@@ -26,17 +25,16 @@
  */
 final class AnonymousClassDefiner implements ClassDefiner {
 
-  private static final Object THE_UNSAFE;
+  private static final sun.misc.Unsafe THE_UNSAFE;
   private static final Method ANONYMOUS_DEFINE_METHOD;
 
   static {
     try {
-      Class<?> unsafeType = Class.forName("sun.misc.Unsafe");
-      Field theUnsafeField = unsafeType.getDeclaredField("theUnsafe");
-      theUnsafeField.setAccessible(true);
-      THE_UNSAFE = theUnsafeField.get(null);
+      THE_UNSAFE = UnsafeGetter.getUnsafe();
+      // defineAnonymousClass was removed in JDK17, so we must refer to it reflectively.
       ANONYMOUS_DEFINE_METHOD =
-          unsafeType.getMethod("defineAnonymousClass", Class.class, byte[].class, Object[].class);
+          sun.misc.Unsafe.class.getMethod(
+              "defineAnonymousClass", Class.class, byte[].class, Object[].class);
     } catch (ReflectiveOperationException e) {
       throw new ExceptionInInitializerError(e);
     }
diff --git a/core/src/com/google/inject/internal/aop/HiddenClassDefiner.java b/core/src/com/google/inject/internal/aop/HiddenClassDefiner.java
index af36f7be0c..1486cb8c93 100644
--- a/core/src/com/google/inject/internal/aop/HiddenClassDefiner.java
+++ b/core/src/com/google/inject/internal/aop/HiddenClassDefiner.java
@@ -28,22 +28,18 @@
  */
 final class HiddenClassDefiner implements ClassDefiner {
 
-  private static final Object THE_UNSAFE;
-  private static final Object TRUSTED_LOOKUP_OFFSET;
-  private static final Method GET_OBJECT_METHOD;
+  private static final sun.misc.Unsafe THE_UNSAFE;
+  private static final Object TRUSTED_LOOKUP_BASE;
+  private static final long TRUSTED_LOOKUP_OFFSET;
   private static final Object HIDDEN_CLASS_OPTIONS;
   private static final Method HIDDEN_DEFINE_METHOD;
 
   static {
     try {
-      Class<?> unsafeType = Class.forName("sun.misc.Unsafe");
-      Field theUnsafeField = unsafeType.getDeclaredField("theUnsafe");
-      theUnsafeField.setAccessible(true);
-      THE_UNSAFE = theUnsafeField.get(null);
+      THE_UNSAFE = UnsafeGetter.getUnsafe();
       Field trustedLookupField = Lookup.class.getDeclaredField("IMPL_LOOKUP");
-      Method offsetMethod = unsafeType.getMethod("staticFieldOffset", Field.class);
-      TRUSTED_LOOKUP_OFFSET = offsetMethod.invoke(THE_UNSAFE, trustedLookupField);
-      GET_OBJECT_METHOD = unsafeType.getMethod("getObject", Object.class, long.class);
+      TRUSTED_LOOKUP_BASE = THE_UNSAFE.staticFieldBase(trustedLookupField);
+      TRUSTED_LOOKUP_OFFSET = THE_UNSAFE.staticFieldOffset(trustedLookupField);
       HIDDEN_CLASS_OPTIONS = classOptions("NESTMATE");
       HIDDEN_DEFINE_METHOD =
           Lookup.class.getMethod(
@@ -56,7 +52,7 @@ final class HiddenClassDefiner implements ClassDefiner {
   @Override
   public Class<?> define(Class<?> hostClass, byte[] bytecode) throws Exception {
     Lookup trustedLookup =
-        (Lookup) GET_OBJECT_METHOD.invoke(THE_UNSAFE, Lookup.class, TRUSTED_LOOKUP_OFFSET);
+        (Lookup) THE_UNSAFE.getObject(TRUSTED_LOOKUP_BASE, TRUSTED_LOOKUP_OFFSET);
     Lookup definedLookup =
         (Lookup)
             HIDDEN_DEFINE_METHOD.invoke(
diff --git a/core/src/com/google/inject/internal/aop/UnsafeGetter.java b/core/src/com/google/inject/internal/aop/UnsafeGetter.java
new file mode 100644
index 0000000000..c7221b658f
--- /dev/null
+++ b/core/src/com/google/inject/internal/aop/UnsafeGetter.java
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2023 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.inject.internal.aop;
+
+final class UnsafeGetter {
+
+  private UnsafeGetter() {}
+
+  static sun.misc.Unsafe getUnsafe() throws ReflectiveOperationException {
+    try {
+      return sun.misc.Unsafe.getUnsafe();
+    } catch (SecurityException unusedFallbackToReflection) {
+    }
+    // Note that we do not do this in a privileged action because we expect we're already in a
+    // privileged block (from UnsafeClassDefiner).
+    Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
+    for (java.lang.reflect.Field f : k.getDeclaredFields()) {
+      f.setAccessible(true);
+      Object x = f.get(null);
+      if (k.isInstance(x)) {
+        return k.cast(x);
+      }
+    }
+    throw new NoSuchFieldError("the Unsafe");
+  }
+}