diff --git a/docs/_code/samples/build.gradle b/docs/_code/samples/build.gradle
index 8b18b57..61bae02 100644
--- a/docs/_code/samples/build.gradle
+++ b/docs/_code/samples/build.gradle
@@ -1,11 +1,11 @@
 /*
- * Copyright 2020, TeamDev. All rights reserved.
+ * Copyright 2026, TeamDev. All rights reserved.
  *
  * 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
+ * https://www.apache.org/licenses/LICENSE-2.0
  *
  * Redistribution and use in source and/or binary forms, with or without
  * modification, must retain the above copyright notice and the following
@@ -30,6 +30,40 @@ plugins {
 
 spine.enableJava().server()
 
+// Spine Bootstrap 1.7.0 (released 2020) injects the now-defunct JCenter as the
+// repository for third-party artifacts such as `protoc`. JCenter is shut down, so
+// nothing resolves from it. Replace it with Maven Central. Spine's own artifacts
+// keep resolving from the `spine.mycloudrepo.io` repositories that Bootstrap also
+// injects, so only the third-party source needs repointing.
+repositories {
+    removeIf { it.name == 'BintrayJCenter' }
+    mavenCentral()
+}
+
+// protoc 3.13.0 and the gRPC codegen plugin 1.28.1 both predate Apple Silicon:
+// no `osx-aarch_64` build of either was ever published to any repository, so
+// resolution fails on arm64 Macs even with a live repo. Force the x86_64 binaries
+// there — they run under Rosetta 2 and keep the tools pinned at exactly the
+// Bootstrap-selected versions, so generated code is identical to every other
+// platform. Everywhere else, keep Bootstrap's auto-detected native binaries.
+def osName = System.getProperty('os.name').toLowerCase()
+def osArch = System.getProperty('os.arch').toLowerCase()
+def appleSilicon = osName.contains('mac') && (osArch == 'aarch64' || osArch == 'arm64')
+protobuf {
+    protoc {
+        if (appleSilicon) {
+            artifact = 'com.google.protobuf:protoc:3.13.0:osx-x86_64@exe'
+        }
+    }
+    plugins {
+        grpc {
+            if (appleSilicon) {
+                artifact = 'io.grpc:protoc-gen-grpc-java:1.28.1:osx-x86_64@exe'
+            }
+        }
+    }
+}
+
 ext {
     junitVersion = '5.7.0'
 }