diff --git a/lib/archunit-0.8.2.jar b/lib/archunit-0.8.2.jar
deleted file mode 100644
index f4ecdcb3..00000000
Binary files a/lib/archunit-0.8.2.jar and /dev/null differ
diff --git a/lib/slf4j-api-1.7.7.jar b/lib/slf4j-api-1.7.7.jar
deleted file mode 100644
index bebabd96..00000000
Binary files a/lib/slf4j-api-1.7.7.jar and /dev/null differ
diff --git a/src/main/groovy/org/aim42/filesystem/FileCollector.groovy b/src/main/groovy/org/aim42/filesystem/FileCollector.groovy
index 359c2964..c5edeb15 100644
--- a/src/main/groovy/org/aim42/filesystem/FileCollector.groovy
+++ b/src/main/groovy/org/aim42/filesystem/FileCollector.groovy
@@ -2,8 +2,6 @@ package org.aim42.filesystem
 
 import groovy.io.FileType
 
-import java.util.regex.Pattern
-
 // see end-of-file for license information
 
 // TODO: add exclude-patterns
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/AllChecksRunner.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/AllChecksRunner.groovy
index 82753416..f39ef4ca 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/AllChecksRunner.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/AllChecksRunner.groovy
@@ -1,16 +1,12 @@
 package org.aim42.htmlsanitycheck
 
-import org.aim42.filesystem.FileCollector
-import org.aim42.filesystem.FileUtil
-import org.aim42.htmlsanitycheck.check.*
+
+import org.aim42.htmlsanitycheck.check.Checker
+import org.aim42.htmlsanitycheck.check.CheckerCreator
 import org.aim42.htmlsanitycheck.collect.PerRunResults
 import org.aim42.htmlsanitycheck.collect.SinglePageResults
 import org.aim42.htmlsanitycheck.html.HtmlPage
-import org.aim42.htmlsanitycheck.report.ConsoleReporter
-import org.aim42.htmlsanitycheck.report.HtmlReporter
-import org.aim42.htmlsanitycheck.report.JUnitXmlReporter
-import org.aim42.htmlsanitycheck.report.LoggerReporter
-import org.aim42.htmlsanitycheck.report.Reporter
+import org.aim42.htmlsanitycheck.report.*
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy
index b033e048..1ec7c303 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy
@@ -1,6 +1,6 @@
 package org.aim42.htmlsanitycheck
 
-import org.aim42.filesystem.FileCollector
+
 import org.aim42.htmlsanitycheck.check.AllCheckers
 import org.aim42.inet.NetUtil
 
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckPlugin.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckPlugin.groovy
index fd519bc5..79f3c546 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckPlugin.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckPlugin.groovy
@@ -2,10 +2,9 @@
 
 package org.aim42.htmlsanitycheck
 
+import org.gradle.api.Plugin
 import org.gradle.api.Project
 import org.gradle.language.base.plugins.LifecycleBasePlugin
-import org.gradle.api.Plugin
-
 
 class HtmlSanityCheckPlugin implements Plugin<Project> {
 
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/check/CheckerCreator.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/check/CheckerCreator.groovy
index a17b7860..e5d7fc93 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/check/CheckerCreator.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/check/CheckerCreator.groovy
@@ -1,7 +1,6 @@
 package org.aim42.htmlsanitycheck.check
 
 import org.aim42.htmlsanitycheck.Configuration
-import org.aim42.htmlsanitycheck.check.UnknownCheckerException
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingImageFilesChecker.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingImageFilesChecker.groovy
index ba69ba3e..46d23487 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingImageFilesChecker.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingImageFilesChecker.groovy
@@ -1,10 +1,10 @@
 package org.aim42.htmlsanitycheck.check
 
 import org.aim42.htmlsanitycheck.Configuration
-import org.aim42.htmlsanitycheck.html.HtmlPage
-import org.aim42.htmlsanitycheck.html.URLUtil
 import org.aim42.htmlsanitycheck.collect.SingleCheckResults
 import org.aim42.htmlsanitycheck.html.HtmlElement
+import org.aim42.htmlsanitycheck.html.HtmlPage
+import org.aim42.htmlsanitycheck.html.URLUtil
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingLocalResourcesChecker.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingLocalResourcesChecker.groovy
index 743c1238..f3988b8b 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingLocalResourcesChecker.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/check/MissingLocalResourcesChecker.groovy
@@ -1,9 +1,9 @@
 package org.aim42.htmlsanitycheck.check
 
-import org.aim42.htmlsanitycheck.html.HtmlPage
-import org.aim42.htmlsanitycheck.html.URLUtil
 import org.aim42.htmlsanitycheck.Configuration
 import org.aim42.htmlsanitycheck.collect.SingleCheckResults
+import org.aim42.htmlsanitycheck.html.HtmlPage
+import org.aim42.htmlsanitycheck.html.URLUtil
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/html/HtmlPage.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/html/HtmlPage.groovy
index 8ed9a94f..d00d13a8 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/html/HtmlPage.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/html/HtmlPage.groovy
@@ -1,12 +1,12 @@
 package org.aim42.htmlsanitycheck.html
 
 import groovy.transform.Memoized
-
-import java.util.regex.Pattern
 import org.jsoup.Jsoup
 import org.jsoup.nodes.Document
 import org.jsoup.select.Elements
 
+import java.util.regex.Pattern
+
 // see end-of-file for license information
 
 /**
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/report/LoggerReporter.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/report/LoggerReporter.groovy
index f65ff7ef..692fc957 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/report/LoggerReporter.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/report/LoggerReporter.groovy
@@ -1,10 +1,7 @@
 package org.aim42.htmlsanitycheck.report
 
 import groovy.transform.InheritConstructors
-import org.aim42.htmlsanitycheck.ProductVersion
 import org.aim42.htmlsanitycheck.collect.PerRunResults
-import org.aim42.htmlsanitycheck.collect.SingleCheckResults
-import org.aim42.htmlsanitycheck.collect.SinglePageResults
 import org.slf4j.Logger
 
 /************************************************************************
diff --git a/src/main/groovy/org/aim42/htmlsanitycheck/suggest/Suggester.groovy b/src/main/groovy/org/aim42/htmlsanitycheck/suggest/Suggester.groovy
index 03cd2edc..10ca9534 100644
--- a/src/main/groovy/org/aim42/htmlsanitycheck/suggest/Suggester.groovy
+++ b/src/main/groovy/org/aim42/htmlsanitycheck/suggest/Suggester.groovy
@@ -1,12 +1,8 @@
-package org.aim42.htmlsanitycheck.suggest;
+package org.aim42.htmlsanitycheck.suggest
 
-import net.ricecode.similarity.JaroWinklerStrategy;
-import net.ricecode.similarity.SimilarityStrategy;
-import net.ricecode.similarity.StringSimilarityService;
-import net.ricecode.similarity.StringSimilarityServiceImpl;
-
-import java.util.ArrayList;
-import java.util.List;
+import net.ricecode.similarity.JaroWinklerStrategy
+import net.ricecode.similarity.StringSimilarityService
+import net.ricecode.similarity.StringSimilarityServiceImpl
 
 /**
  * Finds suggestions for a target within a given list of options by applying string-similarity search
diff --git a/src/main/java/net/ricecode/similarity/StringSimilarityServiceImpl.java b/src/main/java/net/ricecode/similarity/StringSimilarityServiceImpl.java
index 7e6f1bd3..08d0ee0e 100644
--- a/src/main/java/net/ricecode/similarity/StringSimilarityServiceImpl.java
+++ b/src/main/java/net/ricecode/similarity/StringSimilarityServiceImpl.java
@@ -24,9 +24,9 @@
 package net.ricecode.similarity;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
-import java.util.Collections;
 
 
 /**
diff --git a/src/main/java/org/aim42/net/TrustAllCertificates.java b/src/main/java/org/aim42/net/TrustAllCertificates.java
index 21a48c1e..24ed8f79 100644
--- a/src/main/java/org/aim42/net/TrustAllCertificates.java
+++ b/src/main/java/org/aim42/net/TrustAllCertificates.java
@@ -2,7 +2,12 @@
 
 // created by https://www.geekality.net/2013/09/27/java-ignore-ssl-certificate-errors/
 
-import javax.net.ssl.*;
+import javax.net.ssl.HostnameVerifier;
+import javax.net.ssl.HttpsURLConnection;
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.SSLSession;
+import javax.net.ssl.TrustManager;
+import javax.net.ssl.X509TrustManager;
 import java.security.KeyManagementException;
 import java.security.NoSuchAlgorithmException;
 import java.security.cert.X509Certificate;
diff --git a/src/test/groovy/org/aim42/htmlsanitycheck/AllChecksRunnerTest.groovy b/src/test/groovy/org/aim42/htmlsanitycheck/AllChecksRunnerTest.groovy
index 4c88b595..1e8da9dc 100644
--- a/src/test/groovy/org/aim42/htmlsanitycheck/AllChecksRunnerTest.groovy
+++ b/src/test/groovy/org/aim42/htmlsanitycheck/AllChecksRunnerTest.groovy
@@ -2,7 +2,6 @@ package org.aim42.htmlsanitycheck
 
 import org.aim42.htmlsanitycheck.check.AllCheckers
 import org.aim42.htmlsanitycheck.collect.SinglePageResults
-import org.junit.Before
 import org.junit.Test
 
 class AllChecksRunnerTest extends GroovyTestCase {
diff --git a/src/test/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckTaskFunctionalTest.groovy b/src/test/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckTaskFunctionalTest.groovy
index ece54bf5..e15aef48 100644
--- a/src/test/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckTaskFunctionalTest.groovy
+++ b/src/test/groovy/org/aim42/htmlsanitycheck/HtmlSanityCheckTaskFunctionalTest.groovy
@@ -3,7 +3,6 @@ package org.aim42.htmlsanitycheck
 import org.gradle.testkit.runner.GradleRunner
 import org.jsoup.Jsoup
 import org.jsoup.nodes.Element
-import org.jsoup.select.Elements
 import org.junit.Rule
 import org.junit.rules.TemporaryFolder
 import spock.lang.Specification
diff --git a/src/test/groovy/org/aim42/htmlsanitycheck/check/BrokenHttpLinksCheckerSpec.groovy b/src/test/groovy/org/aim42/htmlsanitycheck/check/BrokenHttpLinksCheckerSpec.groovy
index 76ff7912..f73be638 100644
--- a/src/test/groovy/org/aim42/htmlsanitycheck/check/BrokenHttpLinksCheckerSpec.groovy
+++ b/src/test/groovy/org/aim42/htmlsanitycheck/check/BrokenHttpLinksCheckerSpec.groovy
@@ -5,12 +5,11 @@ import org.aim42.htmlsanitycheck.collect.SingleCheckResults
 import org.aim42.htmlsanitycheck.html.HtmlConst
 import org.aim42.htmlsanitycheck.html.HtmlPage
 import org.aim42.inet.NetUtil
-import spock.lang.IgnoreIf
 import spock.lang.Ignore
+import spock.lang.IgnoreIf
 import spock.lang.Specification
 import spock.lang.Unroll
 
-
 // see end-of-file for license information
 
 
diff --git a/src/test/groovy/org/aim42/htmlsanitycheck/check/CheckerCreatorSpec.groovy b/src/test/groovy/org/aim42/htmlsanitycheck/check/CheckerCreatorSpec.groovy
index 0ab0c5af..b2230efa 100644
--- a/src/test/groovy/org/aim42/htmlsanitycheck/check/CheckerCreatorSpec.groovy
+++ b/src/test/groovy/org/aim42/htmlsanitycheck/check/CheckerCreatorSpec.groovy
@@ -3,7 +3,6 @@ package org.aim42.htmlsanitycheck.check
 import org.aim42.htmlsanitycheck.Configuration
 import org.aim42.htmlsanitycheck.html.HtmlPage
 import spock.lang.Specification
-import sun.security.krb5.Config
 
 /**
  * specifiy behavior of CheckerCreator factory
diff --git a/src/test/groovy/org/aim42/htmlsanitycheck/report/JUnitXmlReporterTest.groovy b/src/test/groovy/org/aim42/htmlsanitycheck/report/JUnitXmlReporterTest.groovy
index 32ec2e87..e4cf2a82 100644
--- a/src/test/groovy/org/aim42/htmlsanitycheck/report/JUnitXmlReporterTest.groovy
+++ b/src/test/groovy/org/aim42/htmlsanitycheck/report/JUnitXmlReporterTest.groovy
@@ -6,9 +6,7 @@ import org.aim42.htmlsanitycheck.collect.SingleCheckResults
 import org.aim42.htmlsanitycheck.collect.SinglePageResults
 import org.junit.After
 import org.junit.Before
-import org.junit.Rule
 import org.junit.Test
-import org.junit.rules.TemporaryFolder
 
 // see end-of-file for license information
 
diff --git a/src/test/groovy/org/aim42/htmlsanitycheck/suggest/StringSimilarityServiceImplTest.java b/src/test/groovy/org/aim42/htmlsanitycheck/suggest/StringSimilarityServiceImplTest.java
index 80f36d51..dc722375 100644
--- a/src/test/groovy/org/aim42/htmlsanitycheck/suggest/StringSimilarityServiceImplTest.java
+++ b/src/test/groovy/org/aim42/htmlsanitycheck/suggest/StringSimilarityServiceImplTest.java
@@ -26,7 +26,11 @@
 package org.aim42.htmlsanitycheck.suggest;
 
 
-import net.ricecode.similarity.*;
+import net.ricecode.similarity.JaroWinklerStrategy;
+import net.ricecode.similarity.SimilarityScore;
+import net.ricecode.similarity.SimilarityStrategy;
+import net.ricecode.similarity.StringSimilarityService;
+import net.ricecode.similarity.StringSimilarityServiceImpl;
 import org.junit.Before;
 import org.junit.Test;
 
diff --git a/src/test/java/org/aim42/UnsecureHttpConnection.java b/src/test/java/org/aim42/UnsecureHttpConnection.java
index 585fcf90..c82be19c 100644
--- a/src/test/java/org/aim42/UnsecureHttpConnection.java
+++ b/src/test/java/org/aim42/UnsecureHttpConnection.java
@@ -2,7 +2,6 @@
 
 
 import javax.net.ssl.HttpsURLConnection;
-import java.net.HttpURLConnection;
 import java.net.URL;
 
 public class UnsecureHttpConnection {