diff --git a/packages/workbox-build/src/lib/populate-sw-template.ts b/packages/workbox-build/src/lib/populate-sw-template.ts
index 1a9009d0b..0f00e9858 100644
--- a/packages/workbox-build/src/lib/populate-sw-template.ts
+++ b/packages/workbox-build/src/lib/populate-sw-template.ts
@@ -33,7 +33,7 @@ export function populateSWTemplate({
   skipWaiting,
 }: GeneratePartial & {manifestEntries?: Array<ManifestEntry>}): string {
   // There needs to be at least something to precache, or else runtime caching.
-  if (!(manifestEntries.length > 0 || runtimeCaching.length > 0)) {
+  if (!(manifestEntries?.length > 0 || runtimeCaching.length > 0)) {
     throw new Error(errors['no-manifest-entries-or-runtime-caching']);
   }
 
diff --git a/packages/workbox-webpack-plugin/src/inject-manifest.ts b/packages/workbox-webpack-plugin/src/inject-manifest.ts
index 9c8fa68b5..754ce63a8 100644
--- a/packages/workbox-webpack-plugin/src/inject-manifest.ts
+++ b/packages/workbox-webpack-plugin/src/inject-manifest.ts
@@ -280,7 +280,6 @@ class InjectManifest {
     try {
       this.config = validateWebpackInjectManifestOptions(this.config);
     } catch (error) {
-      // eslint-disable-next-line
       if (error instanceof Error) {
         throw new Error(
           `Please check your ${this.constructor.name} plugin ` +
@@ -380,12 +379,9 @@ class InjectManifest {
     if (
       this.config.compileSrc &&
       // See https://github.com/GoogleChrome/workbox/issues/2729
-      // (TODO: Switch to ?. once our linter supports it.)
       !(
-        compilation.options &&
-        compilation.options.devtool === 'eval-cheap-source-map' &&
-        compilation.options.optimization &&
-        compilation.options.optimization.minimize
+        compilation.options?.devtool === 'eval-cheap-source-map' &&
+        compilation.options.optimization?.minimize
       )
     ) {
       // See https://github.com/GoogleChrome/workbox/issues/2263