diff --git a/build.gradle b/build.gradle
index a216236a..1e887196 100644
--- a/build.gradle
+++ b/build.gradle
@@ -107,12 +107,11 @@ dependencies {
 
 
     testCompile "org.codehaus.groovy:groovy:$groovyVersion"
-    testCompile 'cglib:cglib-nodep:3.2.12'
+    testCompile 'cglib:cglib-nodep:3.3.0'
     testCompile "org.spockframework:spock-core:$spockVersion"
-    testCompile 'de.jodamob.kotlin:kotlin-runner-spock:0.3.1'
     testCompile "io.grpc:grpc-testing:${grpcVersion}"
     testCompile "io.projectreactor:reactor-test:$reactorVersion"
-    testCompile 'org.objenesis:objenesis:3.0.1'
+    testCompile 'org.objenesis:objenesis:3.1'
     testCompile 'org.mock-server:mockserver-netty:5.10'
 }
 
diff --git a/gradle.properties b/gradle.properties
index c5ae5013..6f9e6d14 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -18,5 +18,5 @@ reactorVersion=3.3.3.RELEASE
 etherjarVersion=0.9.1
 
 # Testing
-spockVersion=1.2-groovy-2.5
+spockVersion=1.3-groovy-2.5
 
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcClient.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcClient.kt
index fa58efb3..35ce0d9e 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcClient.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcClient.kt
@@ -10,7 +10,7 @@ import reactor.netty.http.client.HttpClient
 import java.util.*
 import java.util.function.Consumer
 
-class BitcoinRpcClient(
+open class BitcoinRpcClient(
         private val target: String,
         basicAuth: AuthConfig.ClientBasicAuth?
 ) {
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcHeadSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcHeadSpec.groovy
index a8739cfe..0aab0d19 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcHeadSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/bitcoin/BitcoinRpcHeadSpec.groovy
@@ -1,22 +1,14 @@
 package io.emeraldpay.dshackle.upstream.bitcoin
 
-import de.jodamob.kotlin.testrunner.OpenedClasses
-import de.jodamob.kotlin.testrunner.SpotlinTestRunner
 import io.emeraldpay.dshackle.test.TestingCommons
-import org.junit.runner.RunWith
-import org.mockserver.integration.ClientAndServer
 import reactor.core.publisher.Mono
 import reactor.test.StepVerifier
 import spock.lang.Specification
 
 import java.time.Duration
 
-@RunWith(SpotlinTestRunner)
-@OpenedClasses(BitcoinApi)
 class BitcoinRpcHeadSpec extends Specification {
 
-    ClientAndServer mockServer
-
     def "Follow 2 blocks created over 3 requests"() {
         setup:
         String hash1 = "0000000000000000000cf5a5d4dfc4347c0c1a863ec5fdb429b02b2162e50001"