diff --git a/applications/processor/filter-processor/README.adoc b/applications/processor/filter-processor/README.adoc
index db61e062..f29bee77 100644
--- a/applications/processor/filter-processor/README.adoc
+++ b/applications/processor/filter-processor/README.adoc
@@ -16,7 +16,7 @@ If the incoming type is `byte[]` and the content type is set to `text/plain` or
 == Options
 
 //tag::configuration-properties[]
-$$filter.function.expression$$:: $$A SpEL expression to apply.$$ *($$String$$, default: `$$<none>$$`)*
+$$filter.function.expression$$:: $$Boolean SpEL expression to apply against request message to filter.$$ *($$String$$, default: `$$true$$`)*
 //end::configuration-properties[]
 
 //end::ref-doc[]
diff --git a/applications/processor/filter-processor/pom.xml b/applications/processor/filter-processor/pom.xml
index 228444a4..ef6879b4 100644
--- a/applications/processor/filter-processor/pom.xml
+++ b/applications/processor/filter-processor/pom.xml
@@ -20,23 +20,6 @@
             <groupId>org.springframework.cloud.fn</groupId>
             <artifactId>filter-function</artifactId>
         </dependency>
-
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-test</artifactId>
-            <scope>test</scope>
-            <exclusions>
-                <exclusion>
-                    <groupId>org.junit.vintage</groupId>
-                    <artifactId>junit-vintage-engine</artifactId>
-                </exclusion>
-            </exclusions>
-        </dependency>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-json</artifactId>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <build>
diff --git a/functions/function/filter-function/pom.xml b/functions/function/filter-function/pom.xml
index 901a61af..84f586a0 100644
--- a/functions/function/filter-function/pom.xml
+++ b/functions/function/filter-function/pom.xml
@@ -15,6 +15,11 @@
     </parent>
 
     <dependencies>
+        <dependency>
+            <groupId>org.springframework.cloud.fn</groupId>
+            <artifactId>config-common</artifactId>
+            <version>${project.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.springframework.cloud.fn</groupId>
             <artifactId>payload-converter-function</artifactId>
@@ -24,6 +29,10 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-integration</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-json</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-configuration-processor</artifactId>
@@ -40,6 +49,11 @@
                 </exclusion>
             </exclusions>
         </dependency>
+        <dependency>
+            <groupId>io.projectreactor</groupId>
+            <artifactId>reactor-test</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
 </project>
diff --git a/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionConfiguration.java b/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionConfiguration.java
index a935ef9a..a9aba2be 100644
--- a/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionConfiguration.java
+++ b/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionConfiguration.java
@@ -16,39 +16,38 @@
 
 package org.springframework.cloud.fn.filter;
 
-import java.util.Optional;
 import java.util.function.Function;
 
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.integration.transformer.ExpressionEvaluatingTransformer;
 import org.springframework.messaging.Message;
 
+import reactor.core.publisher.Flux;
+
 /**
  * @author Artem Bilan
  * @author David Turanski
  */
-@Configuration
+@Configuration(proxyBeanMethods = false)
 @EnableConfigurationProperties(FilterFunctionProperties.class)
 public class FilterFunctionConfiguration {
 
 	@Bean
-	public Function<Message<?>, Message<?>> filterFunction(
+	public Function<Flux<Message<?>>, Flux<Message<?>>> filterFunction(
 			ExpressionEvaluatingTransformer filterExpressionEvaluatingTransformer) {
 
-		return message -> Optional.of(message)
-				.filter(m -> (Boolean) filterExpressionEvaluatingTransformer.transform(m).getPayload())
-				.orElse(null);
+		return flux ->
+				flux.filter((message) ->
+						(Boolean) filterExpressionEvaluatingTransformer.transform(message).getPayload());
 	}
 
 	@Bean
 	public ExpressionEvaluatingTransformer filterExpressionEvaluatingTransformer(
 			FilterFunctionProperties filterFunctionProperties) {
 
-		return new ExpressionEvaluatingTransformer(new SpelExpressionParser()
-				.parseExpression(filterFunctionProperties.getExpression()));
+		return new ExpressionEvaluatingTransformer(filterFunctionProperties.getExpression());
 	}
 
 }
diff --git a/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionProperties.java b/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionProperties.java
index bde33f71..ab5798d1 100644
--- a/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionProperties.java
+++ b/functions/function/filter-function/src/main/java/org/springframework/cloud/fn/filter/FilterFunctionProperties.java
@@ -18,7 +18,7 @@ package org.springframework.cloud.fn.filter;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.expression.Expression;
-import org.springframework.expression.spel.standard.SpelExpressionParser;
+import org.springframework.integration.expression.ValueExpression;
 
 /**
  * Configuration properties for the SpEL function.
@@ -29,18 +29,16 @@ import org.springframework.expression.spel.standard.SpelExpressionParser;
 @ConfigurationProperties("filter.function")
 public class FilterFunctionProperties {
 
-	private static final Expression DEFAULT_EXPRESSION = new SpelExpressionParser().parseExpression("payload");
-
 	/**
-	 * A SpEL expression to apply.
+	 * Boolean SpEL expression to apply against request message to filter.
 	 */
-	private String expression = DEFAULT_EXPRESSION.getExpressionString();
+	private Expression expression = new ValueExpression<>(true);
 
-	public String getExpression() {
+	public Expression getExpression() {
 		return this.expression;
 	}
 
-	public void setExpression(String expression) {
+	public void setExpression(Expression expression) {
 		this.expression = expression;
 	}
 
diff --git a/functions/function/filter-function/src/main/resources/application.properties b/functions/function/filter-function/src/main/resources/application.properties
deleted file mode 100644
index 86e445ae..00000000
--- a/functions/function/filter-function/src/main/resources/application.properties
+++ /dev/null
@@ -1 +0,0 @@
-spel.function.expression=true
diff --git a/functions/function/filter-function/src/test/java/org/springframework/cloud/fn/filter/FilterFunctionApplicationTests.java b/functions/function/filter-function/src/test/java/org/springframework/cloud/fn/filter/FilterFunctionApplicationTests.java
index ed26dfef..0c8fc873 100644
--- a/functions/function/filter-function/src/test/java/org/springframework/cloud/fn/filter/FilterFunctionApplicationTests.java
+++ b/functions/function/filter-function/src/test/java/org/springframework/cloud/fn/filter/FilterFunctionApplicationTests.java
@@ -30,25 +30,39 @@ import org.springframework.test.annotation.DirtiesContext;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
+import reactor.core.publisher.Flux;
+import reactor.test.StepVerifier;
+
+/**
+ * @author Artem Bilan
+ * @author David Turanski
+ */
 @SpringBootTest(properties = "filter.function.expression=payload.length() > 5")
 @DirtiesContext
 public class FilterFunctionApplicationTests {
 
 	@Autowired
 	@Qualifier("filterFunction")
-	Function<Message<?>, Message<?>> filter;
+	Function<Flux<Message<?>>, Flux<Message<?>>> filter;
 
 	@Test
 	public void testFilter() {
-		Message<?> filtered = this.filter.apply(new GenericMessage<>("hello"));
-		assertThat(filtered).isNull();
-		filtered = this.filter.apply(new GenericMessage<>("hello world"));
-		assertThat(filtered).isNotNull()
-				.extracting(Message::getPayload)
-				.isEqualTo("hello world");
+		Flux<Message<?>> messageFlux =
+				Flux.just("hello", "hello world")
+						.map(GenericMessage::new);
+		Flux<Message<?>> result = this.filter.apply(messageFlux);
+		result
+				.map(Message::getPayload)
+				.cast(String.class)
+				.as(StepVerifier::create)
+				.expectNext("hello world")
+				.expectComplete()
+				.verify();
 	}
 
 	@SpringBootApplication
 	static class FilterFunctionTestApplication {
+
 	}
+
 }