diff --git a/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/internal/GradleVersionUtil.groovy b/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/internal/GradleVersionUtil.groovy
index 8a2f01299..4e54a32cd 100644
--- a/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/internal/GradleVersionUtil.groovy
+++ b/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/internal/GradleVersionUtil.groovy
@@ -2,7 +2,6 @@ package com.github.jengelman.gradle.plugins.shadow.internal
 
 import org.apache.tools.zip.ZipOutputStream
 import org.gradle.api.internal.file.copy.CopySpecInternal
-import org.gradle.api.tasks.WorkResult
 import org.gradle.api.tasks.bundling.Jar
 import org.gradle.api.tasks.bundling.ZipEntryCompression
 import org.gradle.api.tasks.util.PatternSet
@@ -23,20 +22,11 @@ class GradleVersionUtil {
     ZipCompressor getInternalCompressor(ZipEntryCompression entryCompression, Jar jar) {
         switch (entryCompression) {
             case ZipEntryCompression.DEFLATED:
-                return new DefaultZipCompressor(jar.zip64, ZipOutputStream.DEFLATED);
+                return new DefaultZipCompressor(jar.zip64, ZipOutputStream.DEFLATED)
             case ZipEntryCompression.STORED:
-                return new DefaultZipCompressor(jar.zip64, ZipOutputStream.STORED);
+                return new DefaultZipCompressor(jar.zip64, ZipOutputStream.STORED)
             default:
-                throw new IllegalArgumentException(String.format("Unknown Compression type %s", entryCompression));
-        }
-    }
-
-    @SuppressWarnings("deprecation")
-    WorkResult getWorkResult(boolean didWork) {
-        if (version < GradleVersion.version("4.2")) {
-            return new org.gradle.api.internal.tasks.SimpleWorkResult(didWork)
-        } else {
-            org.gradle.api.tasks.WorkResults.didWork(didWork)
+                throw new IllegalArgumentException(String.format("Unknown Compression type %s", entryCompression))
         }
     }
 }
diff --git a/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/DefaultInheritManifest.groovy b/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/DefaultInheritManifest.groovy
index 6f1f0b742..59aab7207 100644
--- a/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/DefaultInheritManifest.groovy
+++ b/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/DefaultInheritManifest.groovy
@@ -1,9 +1,11 @@
 package com.github.jengelman.gradle.plugins.shadow.tasks
 
+import org.gradle.api.Action
 import org.gradle.api.internal.file.FileResolver
 import org.gradle.api.java.archives.Attributes
 import org.gradle.api.java.archives.Manifest
 import org.gradle.api.java.archives.ManifestException
+import org.gradle.api.java.archives.ManifestMergeSpec
 import org.gradle.api.java.archives.internal.DefaultManifest
 import org.gradle.api.java.archives.internal.DefaultManifestMergeSpec
 import org.gradle.util.ConfigureUtil
@@ -88,4 +90,10 @@ class DefaultInheritManifest implements InheritManifest {
         internalManifest.from(o, closure)
         return this
     }
+
+    @Override
+    Manifest from(Object o, Action<ManifestMergeSpec> action) {
+        internalManifest.from(o, action)
+        return this
+    }
 }
diff --git a/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/ShadowCopyAction.groovy b/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/ShadowCopyAction.groovy
index 8a0940a23..d42b3ee34 100644
--- a/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/ShadowCopyAction.groovy
+++ b/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/tasks/ShadowCopyAction.groovy
@@ -30,6 +30,7 @@ import org.gradle.api.internal.file.copy.CopyActionProcessingStream
 import org.gradle.api.internal.file.copy.FileCopyDetailsInternal
 import org.gradle.api.specs.Spec
 import org.gradle.api.tasks.WorkResult
+import org.gradle.api.tasks.WorkResults
 import org.gradle.api.tasks.bundling.Zip
 import org.gradle.api.tasks.util.PatternSet
 import org.gradle.internal.UncheckedException
@@ -95,7 +96,7 @@ class ShadowCopyAction implements CopyAction {
             unusedClasses = Collections.emptySet()
         }
 
-        final ZipOutputStream zipOutStr
+        ZipOutputStream zipOutStr
 
         try {
             zipOutStr = compressor.createArchiveOutputStream(zipFile)
@@ -125,7 +126,7 @@ class ShadowCopyAction implements CopyAction {
                 )
             }
         }
-        return versionUtil.getWorkResult(true)
+        return WorkResults.didWork(true)
     }
 
     private void processTransformers(ZipOutputStream stream) {