diff --git a/release-tools/src/main/java/org/springframework/data/release/build/BuildCommands.java b/release-tools/src/main/java/org/springframework/data/release/build/BuildCommands.java
index 12d0241..0dc1b24 100644
--- a/release-tools/src/main/java/org/springframework/data/release/build/BuildCommands.java
+++ b/release-tools/src/main/java/org/springframework/data/release/build/BuildCommands.java
@@ -53,7 +53,7 @@ class BuildCommands extends TimedCommand {
 	 * 
 	 * @throws IOException
 	 */
-	@CliCommand("workspace purge artifacts")
+	@CliCommand("build purge artifacts")
 	public void purge() throws IOException {
 
 		logger.log("Workspace", "Cleaning up workspace directory at %s.",
diff --git a/release-tools/src/main/java/org/springframework/data/release/build/BuildOperations.java b/release-tools/src/main/java/org/springframework/data/release/build/BuildOperations.java
index da14599..0f5583e 100644
--- a/release-tools/src/main/java/org/springframework/data/release/build/BuildOperations.java
+++ b/release-tools/src/main/java/org/springframework/data/release/build/BuildOperations.java
@@ -121,6 +121,11 @@ public class BuildOperations {
 		return doWithBuildSystem(iteration, (system, module) -> system.prepareVersion(module, phase));
 	}
 
+	/**
+	 * Returns the {@link Path} of the local artifact repository.
+	 * 
+	 * @return
+	 */
 	public Path getLocalRepository() {
 		return properties.getLocalRepository().toPath();
 	}
@@ -135,6 +140,12 @@ public class BuildOperations {
 		return doWithBuildSystem(module, BuildSystem::deploy);
 	}
 
+	/**
+	 * Triggers a nomarl build for the given {@link ModuleIteration}.
+	 * 
+	 * @param module must not be {@literal null}.
+	 * @return
+	 */
 	public ModuleIteration triggerBuild(ModuleIteration module) {
 		return doWithBuildSystem(module, BuildSystem::triggerBuild);
 	}
@@ -177,6 +188,8 @@ public class BuildOperations {
 	 */
 	private <T> T doWithBuildSystem(ModuleIteration module, BiFunction<BuildSystem, ModuleIteration, T> function) {
 
+		Assert.notNull(module, "ModuleIteration must not be null!");
+
 		Supplier<IllegalStateException> exception = () -> new IllegalStateException(
 				String.format("No build system plugin found for project %s!", module.getProject()));
 
diff --git a/release-tools/src/main/java/org/springframework/data/release/build/MavenBuildSystem.java b/release-tools/src/main/java/org/springframework/data/release/build/MavenBuildSystem.java
index d034f67..f8960ab 100644
--- a/release-tools/src/main/java/org/springframework/data/release/build/MavenBuildSystem.java
+++ b/release-tools/src/main/java/org/springframework/data/release/build/MavenBuildSystem.java
@@ -276,6 +276,15 @@ class MavenBuildSystem implements BuildSystem {
 		return module;
 	}
 
+	/* 
+	 * (non-Javadoc)
+	 * @see org.springframework.plugin.core.Plugin#supports(java.lang.Object)
+	 */
+	@Override
+	public boolean supports(Project project) {
+		return isMavenProject(project);
+	}
+
 	/**
 	 * Triggers Maven commands to deploy module artifacts to Spring Artifactory.
 	 * 
@@ -337,15 +346,6 @@ class MavenBuildSystem implements BuildSystem {
 		mvn.execute(module.getProject(), arguments);
 	}
 
-	/* 
-	 * (non-Javadoc)
-	 * @see org.springframework.plugin.core.Plugin#supports(java.lang.Object)
-	 */
-	@Override
-	public boolean supports(Project project) {
-		return isMavenProject(project);
-	}
-
 	private boolean isMavenProject(Project project) {
 		return workspace.getFile(POM_XML, project).exists();
 	}
diff --git a/release-tools/src/main/java/org/springframework/data/release/io/Workspace.java b/release-tools/src/main/java/org/springframework/data/release/io/Workspace.java
index 9c44264..e365f2c 100644
--- a/release-tools/src/main/java/org/springframework/data/release/io/Workspace.java
+++ b/release-tools/src/main/java/org/springframework/data/release/io/Workspace.java
@@ -17,8 +17,10 @@ package org.springframework.data.release.io;
 
 import static org.springframework.data.release.utils.StreamUtils.*;
 
+import lombok.AccessLevel;
 import lombok.NonNull;
 import lombok.RequiredArgsConstructor;
+import lombok.experimental.FieldDefaults;
 
 import java.io.File;
 import java.io.IOException;
@@ -40,6 +42,7 @@ import javax.annotation.PostConstruct;
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.support.ResourcePatternResolver;
 import org.springframework.data.release.model.Project;
+import org.springframework.data.release.utils.Logger;
 import org.springframework.stereotype.Component;
 import org.springframework.util.Assert;
 
@@ -50,12 +53,14 @@ import org.springframework.util.Assert;
  */
 @Component
 @RequiredArgsConstructor
+@FieldDefaults(level = AccessLevel.PRIVATE, makeFinal = true)
 public class Workspace {
 
 	private static final Charset UTF_8 = StandardCharsets.UTF_8;
 
-	private final @NonNull IoProperties ioProperties;
-	private final @NonNull ResourcePatternResolver resolver;
+	@NonNull IoProperties ioProperties;
+	@NonNull ResourcePatternResolver resolver;
+	@NonNull Logger logger;
 
 	/**
 	 * Returns the current working directory.
@@ -73,6 +78,8 @@ public class Workspace {
 	 */
 	public void cleanup() throws IOException {
 
+		logger.log("Workspace", "Cleaning up workspace directory at %s.", getWorkingDirectory().getAbsolutePath());
+
 		Path workingDirPath = getWorkingDirectory().toPath();
 
 		Files.walkFileTree(workingDirPath, new SimpleFileVisitor<Path>() {
diff --git a/release-tools/src/main/java/org/springframework/data/release/io/WorkspaceCommands.java b/release-tools/src/main/java/org/springframework/data/release/io/WorkspaceCommands.java
index 37f553f..76838c8 100644
--- a/release-tools/src/main/java/org/springframework/data/release/io/WorkspaceCommands.java
+++ b/release-tools/src/main/java/org/springframework/data/release/io/WorkspaceCommands.java
@@ -22,6 +22,7 @@ import lombok.experimental.FieldDefaults;
 
 import java.io.IOException;
 
+import org.springframework.data.release.CliComponent;
 import org.springframework.data.release.TimedCommand;
 import org.springframework.data.release.utils.Logger;
 import org.springframework.shell.core.annotation.CliCommand;
@@ -29,6 +30,7 @@ import org.springframework.shell.core.annotation.CliCommand;
 /**
  * @author Oliver Gierke
  */
+@CliComponent
 @RequiredArgsConstructor
 @FieldDefaults(level = AccessLevel.PRIVATE, makeFinal = true)
 class WorkspaceCommands extends TimedCommand {
@@ -38,10 +40,6 @@ class WorkspaceCommands extends TimedCommand {
 
 	@CliCommand("workspace cleanup")
 	public void cleanup() throws IOException {
-
-		logger.log("Workspace", "Cleaning up workspace directory at %s.",
-				workspace.getWorkingDirectory().getAbsolutePath());
-
 		workspace.cleanup();
 	}
 }