diff --git a/packages/domscribe-core/src/lib/constants/index.ts b/packages/domscribe-core/src/lib/constants/index.ts
index 53d3085..a6c28bf 100644
--- a/packages/domscribe-core/src/lib/constants/index.ts
+++ b/packages/domscribe-core/src/lib/constants/index.ts
@@ -79,6 +79,8 @@ export const DEFAULT_CONFIG = {
   RELAY_HOST: '127.0.0.1',
   /** Port to listen on (default: 0 for dynamic port assignment) */
   RELAY_PORT: 0,
+  /** Maximum request body size in bytes (10 MB) */
+  RELAY_BODY_LIMIT: 10 * 1024 * 1024,
   /** Timeout for health check requests in milliseconds */
   RELAY_HEALTH_TIMEOUT_MS: 500,
   /** Maximum time to wait for relay health check in milliseconds */
diff --git a/packages/domscribe-relay/src/server/__test-utils__/setup.ts b/packages/domscribe-relay/src/server/__test-utils__/setup.ts
index 1bfa7a3..98f0434 100644
--- a/packages/domscribe-relay/src/server/__test-utils__/setup.ts
+++ b/packages/domscribe-relay/src/server/__test-utils__/setup.ts
@@ -82,7 +82,7 @@ export async function createTestServer(
   manifestReader.initialize();
 
   // Build Fastify app with same wiring as http-server.ts
-  const app = Fastify({ logger: false });
+  const app = Fastify({ bodyLimit: 10 * 1024 * 1024, logger: false });
   app.decorate('nonce', 'test-nonce');
   app.decorate('relayVersion', RELAY_VERSION);
   app.decorate('workspaceRoot', tempDir);
diff --git a/packages/domscribe-relay/src/server/http-server.ts b/packages/domscribe-relay/src/server/http-server.ts
index 3afe532..fda0fbc 100644
--- a/packages/domscribe-relay/src/server/http-server.ts
+++ b/packages/domscribe-relay/src/server/http-server.ts
@@ -85,6 +85,7 @@ export async function createRelayServer(
 
   // Create Fastify instance
   const app = Fastify({
+    bodyLimit: DEFAULT_CONFIG.RELAY_BODY_LIMIT,
     logger: debug
       ? {
           level: 'info',
diff --git a/packages/domscribe-test-fixtures/fixtures/_templates/webpack-react/package.json__tmpl__ b/packages/domscribe-test-fixtures/fixtures/_templates/webpack-react/package.json__tmpl__
index 324b403..24081d6 100644
--- a/packages/domscribe-test-fixtures/fixtures/_templates/webpack-react/package.json__tmpl__
+++ b/packages/domscribe-test-fixtures/fixtures/_templates/webpack-react/package.json__tmpl__
@@ -23,5 +23,8 @@
     "webpack": "^<%= bundlerVersion %>.0.0",
     "webpack-cli": "^5.1.4",
     "webpack-dev-server": "^5.2.0"
+  },
+  "overrides": {
+    "tapable": "2.3.0"
   }
 }
diff --git a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-js/package.json b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-js/package.json
index 22f5402..72ac155 100644
--- a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-js/package.json
+++ b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-js/package.json
@@ -20,8 +20,11 @@
     "html-webpack-plugin": "^5.6.3",
     "ts-loader": "^9.5.1",
     "typescript": "^5.7.2",
-    "webpack": "^5.0.0",
+    "webpack": "^5.50.0",
     "webpack-cli": "^5.1.4",
     "webpack-dev-server": "^5.2.0"
+  },
+  "overrides": {
+    "tapable": "2.3.0"
   }
 }
diff --git a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-ts/package.json b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-ts/package.json
index 12b67d4..529413f 100644
--- a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-ts/package.json
+++ b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-18-ts/package.json
@@ -23,5 +23,8 @@
     "webpack": "^5.0.0",
     "webpack-cli": "^5.1.4",
     "webpack-dev-server": "^5.2.0"
+  },
+  "overrides": {
+    "tapable": "2.3.0"
   }
 }
diff --git a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-js/package.json b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-js/package.json
index 3099fd4..07cc0ae 100644
--- a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-js/package.json
+++ b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-js/package.json
@@ -23,5 +23,8 @@
     "webpack": "^5.0.0",
     "webpack-cli": "^5.1.4",
     "webpack-dev-server": "^5.2.0"
+  },
+  "overrides": {
+    "tapable": "2.3.0"
   }
 }
diff --git a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-ts/package.json b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-ts/package.json
index db1f567..061c583 100644
--- a/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-ts/package.json
+++ b/packages/domscribe-test-fixtures/fixtures/webpack/v5/react-19-ts/package.json
@@ -23,5 +23,8 @@
     "webpack": "^5.0.0",
     "webpack-cli": "^5.1.4",
     "webpack-dev-server": "^5.2.0"
+  },
+  "overrides": {
+    "tapable": "2.3.0"
   }
 }