diff --git a/lib/normalizer.js b/lib/normalizer.js
index afba412c1..ac3a6ad0c 100644
--- a/lib/normalizer.js
+++ b/lib/normalizer.js
@@ -36,7 +36,7 @@ async function generateProjectTree(options) {
  */
 async function generateDependencyTree(options) {
 	log.verbose("Building dependency tree...");
-	let cwd = options && options.cwd || ".";
+	const cwd = options && options.cwd || ".";
 
 	let translatorName = "npm"; // Default is npm translator
 	let translatorParams = [];
diff --git a/lib/projectPreprocessor.js b/lib/projectPreprocessor.js
index 02fb006cd..1b503e04d 100644
--- a/lib/projectPreprocessor.js
+++ b/lib/projectPreprocessor.js
@@ -347,7 +347,7 @@ class ProjectPreprocessor {
 		if (configurations) {
 			log.verbose(`Project shim ${extension.id} contains ` +
 				`${Object.keys(configurations)} configuration(s)`);
-			for (let projectId in configurations) {
+			for (const projectId in configurations) {
 				if (configurations.hasOwnProperty(projectId)) {
 					this.normalizeConfig(configurations[projectId]); // TODO: Clone object beforehand?
 					if (this.configShims[projectId]) {
@@ -366,7 +366,7 @@ class ProjectPreprocessor {
 
 		if (dependencies) {
 			// For the time being, shimmed dependencies only apply to shimmed project configurations
-			for (let projectId in dependencies) {
+			for (const projectId in dependencies) {
 				if (dependencies.hasOwnProperty(projectId)) {
 					if (this.configShims[projectId]) {
 						log.verbose(`Project shim ${extension.id}: Adding dependencies ` +
@@ -384,7 +384,7 @@ class ProjectPreprocessor {
 		if (collections) {
 			log.verbose(`Project shim ${extension.id} contains ` +
 				`${Object.keys(collections).length} collection(s)`);
-			for (let projectId in collections) {
+			for (const projectId in collections) {
 				if (collections.hasOwnProperty(projectId)) {
 					if (this.collections[projectId]) {
 						log.verbose(`Project shim ${extension.id}: A collection with id '${projectId}' `+
@@ -441,7 +441,7 @@ class ProjectPreprocessor {
 				const collectionDep = project.dependencies[i];
 				const collectionModules = this.collections[depId].modules;
 				const projects = [];
-				for (let projectId in collectionModules) {
+				for (const projectId in collectionModules) {
 					if (collectionModules.hasOwnProperty(projectId)) {
 						// Clone and modify collection "project"
 						const project = JSON.parse(JSON.stringify(collectionDep));
diff --git a/lib/translators/npm.js b/lib/translators/npm.js
index bc84a2f11..0188c6197 100644
--- a/lib/translators/npm.js
+++ b/lib/translators/npm.js
@@ -32,7 +32,7 @@ class NpmTranslator {
 
 		let dependencies = pkg.dependencies || {};
 		let optDependencies = pkg.devDependencies || {};
-		let version = pkg.version;
+		const version = pkg.version;
 
 		// Also look for "napa" dependencies (see https://github.com/shama/napa)
 		if (pkg.napa) {
@@ -44,7 +44,7 @@ class NpmTranslator {
 		const ui5Deps = pkg.ui5 && pkg.ui5.dependencies;
 		if (ui5Deps && ui5Deps.length) {
 			for (let i = 0; i < ui5Deps.length; i++) {
-				let depName = ui5Deps[i];
+				const depName = ui5Deps[i];
 				if (!dependencies[depName] && !optDependencies[depName]) {
 					throw new Error(`[npm translator] Module ${depName} is defined as UI5 dependency ` +
 						`but missing from npm dependencies of module ${moduleName}`);
@@ -55,7 +55,7 @@ class NpmTranslator {
 			dependencies = Object.assign({}, dependencies, optDependencies);
 			optDependencies = {};
 
-			for (let depName in dependencies) {
+			for (const depName in dependencies) {
 				if (dependencies.hasOwnProperty(depName) && ui5Deps.indexOf(depName) === -1) {
 					log.verbose("Ignoring npm dependency %s. Not defined in UI5-dependency configuration.", depName);
 					delete dependencies[depName];
@@ -80,7 +80,7 @@ class NpmTranslator {
 			}).then((depProjects) => {
 				// Array needs to be flattened because:
 				// getDepProjects returns array * 2 = array with two arrays
-				let projects = Array.prototype.concat.apply([], depProjects);
+				const projects = Array.prototype.concat.apply([], depProjects);
 
 				return [{
 					id: moduleName,
@@ -294,7 +294,7 @@ class NpmTranslator {
 			*/
 
 			for (let i = 0; i < tree.length; i++) {
-				let rootPackage = tree[i];
+				const rootPackage = tree[i];
 				if (path.resolve(rootPackage.path) === path.resolve(dirPath)) {
 					log.verbose("Built tree:");
 					log.verbose(rootPackage);