diff --git a/etc/checkstyle/config.xml b/etc/checkstyle/config.xml
index e48bbf6eb..4fc95089a 100644
--- a/etc/checkstyle/config.xml
+++ b/etc/checkstyle/config.xml
@@ -61,7 +61,7 @@
             <property name="illegalPkgs"
                       value="^sun.*, ^org\.apache\.commons\.(?!compress|dbcp2|lang|lang3|logging|pool2).*, ^com\.google\.common.*, ^org\.flywaydb\.core\.internal.*, ^org\.testcontainers\.shaded.*, ^org\.neo4j\.driver\.internal\.shaded.*, ^org\.slf4j.*" />
             <property name="illegalClasses"
-                      value="^reactor\.core\.support\.Assert, ^org\.junit\.rules\.ExpectedException" />
+                      value="^reactor\.core\.support\.Assert, ^org\.junit\.rules\.ExpectedException, ^org\.junit\.Test" />
         </module>
         <module name="com.puppycrawl.tools.checkstyle.checks.imports.RedundantImportCheck" />
         <module name="com.puppycrawl.tools.checkstyle.checks.imports.UnusedImportsCheck">
diff --git a/spring-data-neo4j/pom.xml b/spring-data-neo4j/pom.xml
index a64f7574c..da8b69fad 100644
--- a/spring-data-neo4j/pom.xml
+++ b/spring-data-neo4j/pom.xml
@@ -133,6 +133,12 @@
 			<artifactId>kotlin-reflect</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>io.mockk</groupId>
+			<artifactId>mockk</artifactId>
+			<version>${mockk}</version>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.testcontainers</groupId>
 			<artifactId>junit-jupiter</artifactId>
diff --git a/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Conditions.java b/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Conditions.java
index 896bb5fc7..59858dd91 100644
--- a/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Conditions.java
+++ b/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Conditions.java
@@ -188,19 +188,6 @@ public final class Conditions {
 		return Comparison.create(Operator.IS_NOT_NULL, expression);
 	}
 
-	/**
-	 * Creates a condition that checkts whether the expression {@code searchFor} is in the expression {@code in}.
-	 * {@code in} is supposed to represent a list object.
-	 *
-	 * @param searchFor The expression to search for.
-	 * @param in        The expression to search in.
-	 * @return A new condition.
-	 */
-	static Condition in(Expression searchFor, Expression in) {
-
-		return Comparison.create(searchFor, Operator.IN, in);
-	}
-
 	/**
 	 * A condition that evaluates to true if a list or a string represented by {@code expression} is empty or has the length of 0.
 	 *
@@ -223,7 +210,6 @@ public final class Conditions {
 		return new BooleanFunctionCondition(Functions.exists(expression));
 	}
 
-
 	/**
 	 * Not to be instantiated.
 	 */
diff --git a/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Expression.java b/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Expression.java
index 56fa486d1..633b1c653 100644
--- a/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Expression.java
+++ b/spring-data-neo4j/src/main/java/org/neo4j/springframework/data/core/cypher/Expression.java
@@ -171,11 +171,11 @@ public interface Expression extends Visitable {
 	 * Creates a {@code IN} operation for this expression and that {@code expression}.
 	 * The expression does not track the condition created here.
 	 *
-	 * @param expression The expression to search for this expression
+	 * @param haystack The expression to search for this expression
 	 * @return A new condition.
 	 */
-	default Condition in(Expression expression) {
-		return Conditions.in(this, expression);
+	default Condition in(Expression haystack) {
+		return Comparison.create(this, Operator.IN, haystack);
 	}
 
 	/**
diff --git a/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/Neo4jClientExtensions.kt b/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/Neo4jClientExtensions.kt
new file mode 100644
index 000000000..53b432672
--- /dev/null
+++ b/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/Neo4jClientExtensions.kt
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2019 "Neo4j,"
+ * Neo4j Sweden AB [https://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.springframework.data.core
+
+/**
+ * Extension for [Neo4jClient.RunnableSpec.in] providing an `inDatabase` alias since `in` is a reserved keyword in Kotlin.
+ *
+ * @author Michael J. Simons
+ * @since 1.0
+ */
+fun Neo4jClient.RunnableSpec.inDatabase(targetDatabase: String): Neo4jClient.RunnableSpecTightToDatabase = `in`(targetDatabase)
+
+/**
+ * Extension for [Neo4jClient.OngoingDelegation.in] providing an `inDatabase` alias since `in` is a reserved keyword in Kotlin.
+ *
+ * @author Michael J. Simons
+ * @since 1.0
+ */
+fun <T : Any?> Neo4jClient.OngoingDelegation<T>.inDatabase(targetDatabase: String): Neo4jClient.RunnableDelegation<T> = `in`(targetDatabase)
diff --git a/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/ReactiveNeo4jClientExtensions.kt b/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/ReactiveNeo4jClientExtensions.kt
new file mode 100644
index 000000000..a7f1ab6bb
--- /dev/null
+++ b/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/ReactiveNeo4jClientExtensions.kt
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2019 "Neo4j,"
+ * Neo4j Sweden AB [https://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.springframework.data.core
+
+/**
+ * Extension for [ReactiveNeo4jClient.ReactiveRunnableSpec.in] providing an `inDatabase` alias since `in` is a reserved keyword in Kotlin.
+ *
+ * @author Michael J. Simons
+ * @since 1.0
+ */
+fun ReactiveNeo4jClient.ReactiveRunnableSpec.inDatabase(targetDatabase: String): ReactiveNeo4jClient.ReactiveRunnableSpecTightToDatabase = `in`(targetDatabase)
+
+/**
+ * Extension for [ReactiveNeo4jClient.OngoingReactiveDelegation.in] providing an `inDatabase` alias since `in` is a reserved keyword in Kotlin.
+ *
+ * @author Michael J. Simons
+ * @since 1.0
+ */
+fun <T : Any?> ReactiveNeo4jClient.OngoingReactiveDelegation<T>.inDatabase(targetDatabase: String): ReactiveNeo4jClient.ReactiveRunnableDelegation<T> = `in`(targetDatabase)
diff --git a/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/cypher/CypherExtensions.kt b/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/cypher/CypherExtensions.kt
new file mode 100644
index 000000000..c4a700496
--- /dev/null
+++ b/spring-data-neo4j/src/main/kotlin/org/neo4j/springframework/data/core/cypher/CypherExtensions.kt
@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2019 "Neo4j,"
+ * Neo4j Sweden AB [https://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.springframework.data.core.cypher
+
+/**
+ * Extension for [Expression.in] providing an `inValues` alias since `in` is a reserved keyword in Kotlin.
+ *
+ * @author Michael J. Simons
+ * @since 1.0
+ */
+fun Expression.inValues(inHaystack: Expression): Condition = `in`(inHaystack)
+
+/**
+ * Extension for [Expression.as] providing an `withAlias` alias since `as` is a reserved keyword in Kotlin.
+ *
+ * @author Michael J. Simons
+ * @since 1.0
+ */
+fun Expression.asAlias(alias: String): AliasedExpression = `as`(alias)
+
+fun StatementBuilder.OngoingUnwind.asAlias(alias: String): StatementBuilder.OngoingReading = `as`(alias)
diff --git a/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/Neo4jClientExtensionsTest.kt b/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/Neo4jClientExtensionsTest.kt
new file mode 100644
index 000000000..0c84724af
--- /dev/null
+++ b/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/Neo4jClientExtensionsTest.kt
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2019 "Neo4j,"
+ * Neo4j Sweden AB [https://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.springframework.data.core
+
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Test
+
+/**
+ * @author Michael J. Simons
+ */
+class Neo4jClientExtensionsTest {
+
+	@Test
+	fun `RunnableSpec#inDatabase(targetDatabase) extension should call its Java counterpart`() {
+
+		val runnableSpec = mockk<Neo4jClient.RunnableSpec>(relaxed = true)
+
+		runnableSpec.inDatabase("foobar");
+
+		verify(exactly = 1) { runnableSpec.`in`("foobar") }
+	}
+
+	@Test
+	fun `OngoingDelegation#inDatabase(targetDatabase) extension should call its Java counterpart`() {
+
+		val ongoingDelegation = mockk<Neo4jClient.OngoingDelegation<Any>>(relaxed = true)
+
+		ongoingDelegation.inDatabase("foobar");
+
+		verify(exactly = 1) { ongoingDelegation.`in`("foobar") }
+	}
+}
\ No newline at end of file
diff --git a/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/ReactiveNeo4jClientExtensionsTest.kt b/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/ReactiveNeo4jClientExtensionsTest.kt
new file mode 100644
index 000000000..85f72a511
--- /dev/null
+++ b/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/ReactiveNeo4jClientExtensionsTest.kt
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2019 "Neo4j,"
+ * Neo4j Sweden AB [https://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.springframework.data.core
+
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Test
+
+/**
+ * @author Michael J. Simons
+ */
+class ReactiveNeo4jClientExtensionsTest {
+
+	@Test
+	fun `RunnableSpec#inDatabase(targetDatabase) extension should call its Java counterpart`() {
+
+		val runnableSpec = mockk<ReactiveNeo4jClient.ReactiveRunnableSpec>(relaxed = true)
+
+		runnableSpec.inDatabase("foobar");
+
+		verify(exactly = 1) { runnableSpec.`in`("foobar") }
+	}
+
+	@Test
+	fun `OngoingDelegation#inDatabase(targetDatabase) extension should call its Java counterpart`() {
+
+		val ongoingDelegation = mockk<ReactiveNeo4jClient.OngoingReactiveDelegation<Any>>(relaxed = true)
+
+		ongoingDelegation.inDatabase("foobar");
+
+		verify(exactly = 1) { ongoingDelegation.`in`("foobar") }
+	}
+}
\ No newline at end of file
diff --git a/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/cypher/CypherExtensionsTest.kt b/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/cypher/CypherExtensionsTest.kt
new file mode 100644
index 000000000..127e01efc
--- /dev/null
+++ b/spring-data-neo4j/src/test/kotlin/org/neo4j/springframework/data/core/cypher/CypherExtensionsTest.kt
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2019 "Neo4j,"
+ * Neo4j Sweden AB [https://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.springframework.data.core.cypher
+
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+import org.neo4j.springframework.data.core.cypher.Cypher.listOf
+import org.neo4j.springframework.data.core.cypher.Cypher.literalFalse
+
+/**
+ * @author Michael J. Simons
+ */
+class CypherExtensionsTest {
+
+	@Nested
+	inner class ExpressionExtensions {
+		val expression = mockk<Expression>(relaxed = true)
+
+		@Test
+		fun `inValues(expression) extension should call its Java counterpart`() {
+
+			expression.inValues(listOf(literalFalse()));
+
+			verify(exactly = 1) { expression.`in`(any()) }
+		}
+
+		@Test
+		fun `asAlias(alias) extension should call its Java counterpart`() {
+
+			expression.asAlias("foo")
+
+			verify(exactly = 1) { expression.`as`("foo") }
+		}
+	}
+
+	@Nested
+	inner class StatementBuilderExtensions {
+
+		@Test
+		fun `asAlias(alias) extension should call its Java counterpart`() {
+			val ongoingUnwind = mockk<StatementBuilder.OngoingUnwind>(relaxed = true)
+
+			ongoingUnwind.asAlias("foo")
+
+			verify(exactly = 1) { ongoingUnwind.`as`("foo") }
+		}
+	}
+}