diff --git a/build.gradle b/build.gradle
index 4c8e076..76208cb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -19,13 +19,20 @@ repositories {
 }
 
 dependencies {
+
+    implementation("org.slf4j:slf4j-api:${slf4jVersion}")
     implementation("org.slf4j:slf4j-simple:${slf4jVersion}")
     implementation('com.google.code.gson:gson:2.8.5')
     implementation("com.squareup.okhttp3:okhttp:4.1.0")
+
+    testCompile("org.codehaus.groovy:groovy-all:${groovyVersion}")
     testCompile("org.spockframework:spock-core:${spockVersion}") {
         exclude group: "org.codehaus.groovy"
     }
-    testCompile group: 'com.athaydes', name: 'spock-reports', version: '1.3.1'
+    testCompile( 'com.athaydes:spock-reports:1.6.2' ) {
+        transitive = false // this avoids affecting your version of Groovy/Spock
+    }
+
 }
 
 bintray {
diff --git a/gradle.properties b/gradle.properties
index 89c4a05..843a23f 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -3,7 +3,7 @@ group         = biz.nellemann.libs
 version       = 1.0.1
 licenses      = ['APACHE-2.0'] // or something else 
 groovyVersion = 2.5.8
-slf4jVersion  = 1.7.25
-spockVersion  = 1.2-groovy-2.5
+slf4jVersion  = 1.7.28
+spockVersion  = 1.3-groovy-2.5
 siteUrl       = https://bitbucket.org/mnellemann/libcvrapi
 gitUrl        = https://bitbucket.org/mnellemann/libcvrapi.git