diff --git a/Justfile b/Justfile
index 2522911e09..562d618cea 100644
--- a/Justfile
+++ b/Justfile
@@ -4,7 +4,7 @@ dev: install-jars
 
 # Install all JARs to local Maven repository and local build directory
 install-jars:
-  bit 'build/**/*.jar'
+  bit 'kotlin-runtime/**/*.jar'
 
 # Deploy the Go time module
 deploy-time:
diff --git a/buildengine/deps.go b/buildengine/deps.go
index 9e5dcd0137..aee06c4f1d 100644
--- a/buildengine/deps.go
+++ b/buildengine/deps.go
@@ -99,7 +99,7 @@ func extractKotlinFTLImports(self, dir string) ([]string, error) {
 	dependencies := map[string]bool{}
 	kotlinImportRegex := regexp.MustCompile(`^import ftl\.([A-Za-z0-9_.]+)`)
 
-	err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {
+	err := filepath.WalkDir(filepath.Join(dir, "src/main/kotlin"), func(path string, d fs.DirEntry, err error) error {
 		if err != nil {
 			return err
 		}
@@ -127,7 +127,7 @@ func extractKotlinFTLImports(self, dir string) ([]string, error) {
 	})
 
 	if err != nil {
-		return nil, fmt.Errorf("%s: failed to extract dependencies from Go module: %w", self, err)
+		return nil, fmt.Errorf("%s: failed to extract dependencies from Kotlin module: %w", self, err)
 	}
 	modules := maps.Keys(dependencies)
 	sort.Strings(modules)
diff --git a/buildengine/testdata/modules/alphakotlin/Alpha.kt b/buildengine/testdata/modules/alphakotlin/src/main/kotlin/ftl/alpha/Alpha.kt
similarity index 95%
rename from buildengine/testdata/modules/alphakotlin/Alpha.kt
rename to buildengine/testdata/modules/alphakotlin/src/main/kotlin/ftl/alpha/Alpha.kt
index f3d80703ee..722a78f183 100644
--- a/buildengine/testdata/modules/alphakotlin/Alpha.kt
+++ b/buildengine/testdata/modules/alphakotlin/src/main/kotlin/ftl/alpha/Alpha.kt
@@ -1,4 +1,4 @@
-package ftl.echo
+package ftl.alpha
 
 import ftl.builtin.Empty
 import ftl.other.Other