diff --git a/src/playwright-runner.ts b/src/playwright-runner.ts
index 6b44f751..50b2ee98 100644
--- a/src/playwright-runner.ts
+++ b/src/playwright-runner.ts
@@ -177,7 +177,7 @@ async function getCfg(
   runCfg.sauce.region = runCfg.sauce.region || 'us-west-1';
   runCfg.playwrightOutputFolder =
     suite.env?.SAUCE_SYNC_WEB_ASSETS?.toLowerCase() === 'true'
-      ? ''
+      ? undefined
       : path.join(runCfg.assetsDir, 'test-results');
 
   runCfg.webAssetsDir =
diff --git a/src/types.ts b/src/types.ts
index 108c10e1..54ddc373 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -27,9 +27,9 @@ export interface RunnerConfig {
   preExecTimeout: number;
   path: string;
   projectPath: string;
-  playwrightOutputFolder: string;
+  playwrightOutputFolder?: string;
   // webAssetsDir contains assets compatible with the Sauce Labs web UI.
-  webAssetsDir: string;
+  webAssetsDir?: string;
   suite: Suite;
 
   args: Record<string, unknown>;
diff --git a/src/utils.ts b/src/utils.ts
index 5f050044..d070cdc1 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -51,7 +51,9 @@ export function replaceLegacyKeys(config: SuiteConfig) {
   return args;
 }
 
-export function setEnvironmentVariables(envVars: Record<string, string> = {}) {
+export function setEnvironmentVariables(
+  envVars: Record<string, string | undefined> = {},
+) {
   if (!envVars) {
     return;
   }