diff --git a/lib/index.ts b/lib/index.ts
index b91c88a9..8f5e0d1c 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -49,9 +49,9 @@ function buildDepTreeFromFiles(
 
   const manifestFileContents = fs.readFileSync(manifestFileFullPath, 'utf-8');
 
-  if (manifestFilePath.endsWith('.csproj')) {
+  if (_.endsWith(manifestFilePath, '.csproj')) {
     return buildDepTreeFromCsproj(manifestFileContents, includeDev);
-  } else if (manifestFilePath.endsWith('packages.config')) {
+  } else if (_.endsWith(manifestFilePath, 'packages.config')) {
     return buildDepTreeFromPackagesConfig(manifestFileContents, includeDev);
   } else {
     throw new Error(`Unsupported file ${manifestFilePath},
diff --git a/package.json b/package.json
index 60b6b6fc..fa6afd4f 100644
--- a/package.json
+++ b/package.json
@@ -29,11 +29,12 @@
     "@types/xml2js": "0.4.3",
     "lodash": "4.17.10",
     "source-map-support": "^0.5.7",
+    "tslib": "^1.9.3",
     "xml2js": "0.4.19"
   },
   "devDependencies": {
     "@types/lodash": "^4.14.116",
-    "@types/node": "10.5.5",
+    "@types/node": "^4.0.47",
     "tap": "github:snyk/node-tap#alternative-runtimes",
     "ts-node": "7.0.0",
     "tslint": "5.11.0",
diff --git a/tsconfig.json b/tsconfig.json
index 81f943b0..c9141d4f 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -3,16 +3,15 @@
         "outDir": "./dist",
         "pretty": true,
         "target": "es5",
-        "lib": [
-          "es2017"
-        ],
+        "lib": ["es5", "es2015.promise"],
         "module": "commonjs",
         "sourceMap": true,
         "declaration": true,
+        "importHelpers": true,
         "strict": true,
         "noImplicitAny": false // Needed to compile tap
     },
     "include": [
-        "./lib/**/*",
+        "./lib/**/*"
     ]
 }