diff --git a/README.md b/README.md
index 128edb4..616e2c8 100644
--- a/README.md
+++ b/README.md
@@ -75,7 +75,8 @@ export default () => {
 
 xk6-ts can be disabled by setting the `XK6_TS` environment variable to `false`.
 
-During the development of the test script, it is recommended to set the `XK6_TS_SOURCEMAP` environment variable to `true`. Thus, the runtime error messages will report the correct source code position. Otherwise, due to transpilation and bundling, the source code position is meaningless.
+To ensure that runtime error messages report the correct source code position, sourcemap generation is enabled by default. Otherwise, due to transpilation and bundling, the source code position is meaningless.
+Sourcemap generation can be disabled by setting the value of the `XK6_TS_SOURCEMAP` environment variable to `false`.
 
 ## Features
 
diff --git a/loader.go b/loader.go
index 91a8c54..305c680 100644
--- a/loader.go
+++ b/loader.go
@@ -57,7 +57,7 @@ func redirectStdin() {
 
 	opts := &k6pack.Options{
 		Filename:  filename,
-		SourceMap: os.Getenv("XK6_TS_SOURCEMAP") == "true",
+		SourceMap: os.Getenv("XK6_TS_SOURCEMAP") != "false",
 	}
 
 	source, err := os.ReadFile(filepath.Clean(filename))