diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index a0c1e404ca..af8a43094c 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -12,9 +12,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v1
-      - name: Set up JDK 1.8
+      - name: Set up Java 11
         uses: actions/setup-java@v1
         with:
-          java-version: 1.8
+          java-version: '11.0.2'
       - name: Build with Maven
-        run: mvn clean verify -PdefaultBuild -P!jdk8
+        run: ./mvnw clean verify -PdefaultBuild
diff --git a/graphql-kotlin-federation/src/main/kotlin/com/expediagroup/graphql/federation/FederatedSchemaGenerator.kt b/graphql-kotlin-federation/src/main/kotlin/com/expediagroup/graphql/federation/FederatedSchemaGenerator.kt
index c16f74dfc1..7231af3dbf 100644
--- a/graphql-kotlin-federation/src/main/kotlin/com/expediagroup/graphql/federation/FederatedSchemaGenerator.kt
+++ b/graphql-kotlin-federation/src/main/kotlin/com/expediagroup/graphql/federation/FederatedSchemaGenerator.kt
@@ -61,6 +61,9 @@ open class FederatedSchemaGenerator(generatorConfig: FederatedSchemaGeneratorCon
             .forEach {
                 this.additionalType(it)
             }
+
+        scanResult.close()
+
         return this
     }
 }
diff --git a/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SchemaGenerator.kt b/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SchemaGenerator.kt
index 8540b2f79b..275abaa13a 100644
--- a/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SchemaGenerator.kt
+++ b/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SchemaGenerator.kt
@@ -86,7 +86,13 @@ open class SchemaGenerator(val config: SchemaGeneratorConfig) {
 
         builder.additionalDirectives(state.directives.values.toSet())
         builder.codeRegistry(codeRegistry.build())
-        return config.hooks.willBuildSchema(builder).build()
+
+        val schema = config.hooks.willBuildSchema(builder).build()
+
+        // Clean up the classpath scanner
+        subTypeMapper.close()
+
+        return schema
     }
 
     open fun function(fn: KFunction<*>, parentName: String, target: Any? = null, abstract: Boolean = false) =
diff --git a/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SubTypeMapper.kt b/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SubTypeMapper.kt
index 78828dc34d..3b86d86a54 100644
--- a/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SubTypeMapper.kt
+++ b/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SubTypeMapper.kt
@@ -39,6 +39,8 @@ internal class SubTypeMapper(supportedPackages: List<String>) {
             .filterNot { it.isAbstract }
     }
 
+    fun close() = scanResult.close()
+
     @Suppress("Detekt.SwallowedException")
     private fun getImplementingClasses(classInfo: ClassInfo) =
         try {
diff --git a/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/state/TypesCache.kt b/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/state/TypesCache.kt
index 0dbb1320eb..dc2b23c6b8 100644
--- a/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/state/TypesCache.kt
+++ b/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/state/TypesCache.kt
@@ -62,6 +62,11 @@ internal class TypesCache(private val supportedPackages: List<String>) {
         return null
     }
 
+    /**
+     * Clear the map of all saved values
+     */
+    internal fun clear() = cache.clear()
+
     fun doesNotContainGraphQLType(graphQLType: GraphQLType) =
         cache.none { (_, v) -> v.graphQLType.name == graphQLType.name }
 
diff --git a/graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/types/TypeTestHelper.kt b/graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/types/TypeTestHelper.kt
index 88a5999439..6b91e50406 100644
--- a/graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/types/TypeTestHelper.kt
+++ b/graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/types/TypeTestHelper.kt
@@ -30,6 +30,10 @@ import graphql.schema.GraphQLCodeRegistry
 import io.mockk.every
 import io.mockk.mockk
 import io.mockk.spyk
+import org.junit.jupiter.api.AfterAll
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.TestInstance
+import org.junit.jupiter.api.TestInstance.Lifecycle
 import java.lang.reflect.Field
 import kotlin.reflect.KAnnotatedElement
 import kotlin.reflect.KClass
@@ -37,18 +41,18 @@ import kotlin.reflect.KFunction
 import kotlin.reflect.KParameter
 import kotlin.reflect.KProperty
 import kotlin.reflect.KType
-import kotlin.test.BeforeTest
 
 @Suppress(
     "Detekt.UnsafeCast",
     "Detekt.UnsafeCallOnNullableType",
     "Detekt.LongMethod"
 )
+@TestInstance(Lifecycle.PER_CLASS)
 internal open class TypeTestHelper {
+    private val subTypeMapper = SubTypeMapper(listOf("com.expediagroup.graphql"))
     var generator = mockk<SchemaGenerator>()
     var config = mockk<SchemaGeneratorConfig>()
     var state = spyk(SchemaGeneratorState(listOf("com.expediagroup.graphql")))
-    var subTypeMapper = spyk(SubTypeMapper(listOf("com.expediagroup.graphql")))
     var cache = spyk(TypesCache(listOf("com.expediagroup.graphql")))
     val spyWiringFactory = spyk(KotlinDirectiveWiringFactory())
     var hooks: SchemaGeneratorHooks = object : SchemaGeneratorHooks {
@@ -69,10 +73,12 @@ internal open class TypeTestHelper {
     private var argumentBuilder: ArgumentBuilder? = null
     private var inputObjectBuilder: InputObjectBuilder? = null
 
-    @BeforeTest
+    @BeforeEach
     fun setup() {
         beforeSetup()
 
+        cache.clear()
+
         every { generator.state } returns state
         every { state.cache } returns cache
         every { generator.config } returns config
@@ -157,6 +163,11 @@ internal open class TypeTestHelper {
         beforeTest()
     }
 
+    @AfterAll
+    fun cleanup() {
+        subTypeMapper.close()
+    }
+
     open fun beforeTest() {}
 
     open fun beforeSetup() {}