diff --git a/deploy/lib/setIamPolicy.js b/deploy/lib/setIamPolicy.js
index c584ed2..d2bf7cc 100644
--- a/deploy/lib/setIamPolicy.js
+++ b/deploy/lib/setIamPolicy.js
@@ -1,7 +1,7 @@
 'use strict';
 
-const _ = require('lodash');
 const BbPromise = require('bluebird');
+const ServerlessError = require('serverless/lib/classes/Error').ServerlessError;
 
 module.exports = {
   setIamPolicy() {
@@ -33,37 +33,40 @@ module.exports = {
     }
     this.serverless.cli.log('Setting IAM policies...');
 
-    _.forEach(policies, (value, key) => {
+    const promises = [];
+    Object.entries(policies).forEach((entry) => {
       const func = functions.find((fn) => {
-        return fn.name === key;
+        return fn.name === entry[0];
       });
       if (func) {
         const params = {
           resource: func.name,
           requestBody: {
             policy: {
-              bindings: value,
+              bindings: entry[1],
             },
           },
         };
 
-        this.provider.request(
-          'cloudfunctions',
-          'projects',
-          'locations',
-          'functions',
-          'setIamPolicy',
-          params
+        promises.push(
+          this.provider.request(
+            'cloudfunctions',
+            'projects',
+            'locations',
+            'functions',
+            'setIamPolicy',
+            params
+          )
         );
       } else {
         const errorMessage = [
-          `Unable to set IAM bindings (${value}) for "${key}": function not found for`,
+          `Unable to set IAM bindings (${entry[1]}) for "${entry[0]}": function not found for`,
           ` project "${this.serverless.service.provider.project}" in region "${this.options.region}".`,
         ].join('');
-        throw new Error(errorMessage);
+        throw new ServerlessError(errorMessage);
       }
     });
 
-    return BbPromise.resolve();
+    return BbPromise.all(promises);
   },
 };
diff --git a/package.json b/package.json
index 62ff5c9..65e5f74 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,8 @@
     "chalk": "^3.0.0",
     "fs-extra": "^8.1.0",
     "googleapis": "^50.0.0",
-    "lodash": "^4.17.15"
+    "lodash": "^4.17.15",
+    "serverless": "^1.74.1"
   },
   "devDependencies": {
     "@commitlint/cli": "^8.3.5",
diff --git a/package/lib/compileFunctions.js b/package/lib/compileFunctions.js
index d23d3ce..756f297 100644
--- a/package/lib/compileFunctions.js
+++ b/package/lib/compileFunctions.js
@@ -62,20 +62,17 @@ module.exports = {
       // Collect the configured IAM bindings at the function and provider level and merge the
       // members for each defined role. This transforms the array of IAM bindings into a mapping
       // in order to easily merge.
-      const iamBindings = _.reduce(
-        _.concat(
-          _.get(funcObject, 'iam.bindings') || [],
+      const iamBindings = (_.get(funcObject, 'iam.bindings') || [])
+        .concat(
           _.get(this, 'serverless.service.provider.iam.bindings') || [],
           allowUnauthenticated
             ? [{ role: 'roles/cloudfunctions.invoker', members: ['allUsers'] }]
             : []
-        ),
-        (result, value) => {
+        )
+        .reduce((result, value) => {
           result[value.role] = _.union(result[value.role] || [], value.members);
           return result;
-        },
-        {}
-      );
+        }, {});
 
       if (!funcTemplate.properties.serviceAccountEmail) {
         delete funcTemplate.properties.serviceAccountEmail;