diff --git a/kyaml/fn/framework/doc.go b/kyaml/fn/framework/doc.go
index 9691e10d3..adf83047f 100644
--- a/kyaml/fn/framework/doc.go
+++ b/kyaml/fn/framework/doc.go
@@ -31,7 +31,7 @@
 //
 // Validator Functions
 //
-// Functions may validate resources, returning Results as go errors.  Results may contain
+// Functions may validate resources, returning results as go errors.  results may contain
 // different items for different validation failures.
 //
 // Configuring Functions
diff --git a/kyaml/fn/framework/example_test.go b/kyaml/fn/framework/example_test.go
index e54bf3538..10f96e1d7 100644
--- a/kyaml/fn/framework/example_test.go
+++ b/kyaml/fn/framework/example_test.go
@@ -281,7 +281,7 @@ functionConfig:
 }
 
 // ExampleCommand_validate validates that all Deployment resources have the replicas field set.
-// If any Deployments do not contain spec.replicas, then the function will return Results
+// If any Deployments do not contain spec.replicas, then the function will return results
 // which will be set on ResourceList.results
 func ExampleCommand_validate() {
 	cmd := framework.Command(nil, func(nodes []*yaml.RNode) ([]*yaml.RNode, error) {
@@ -320,7 +320,7 @@ func ExampleCommand_validate() {
 			})
 		}
 
-		// framework will only consider Results an error if it has at least 1 item
+		// framework will only consider results an error if it has at least 1 item
 		return nodes, framework.Result{
 			Name:  "replicas-validator",
 			Items: validationResults,
diff --git a/kyaml/fn/runtime/exec/doc.go b/kyaml/fn/runtime/exec/doc.go
new file mode 100644
index 000000000..2747a96fb
--- /dev/null
+++ b/kyaml/fn/runtime/exec/doc.go
@@ -0,0 +1,5 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+// Package exec contains the exec function implementation.
+package exec
diff --git a/kyaml/fn/runtime/exec/exec.go b/kyaml/fn/runtime/exec/exec.go
new file mode 100644
index 000000000..cf8edeaa5
--- /dev/null
+++ b/kyaml/fn/runtime/exec/exec.go
@@ -0,0 +1,34 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package exec
+
+import (
+	"io"
+	"os/exec"
+
+	"sigs.k8s.io/kustomize/kyaml/fn/runtime/runtimeutil"
+	"sigs.k8s.io/kustomize/kyaml/yaml"
+)
+
+type Filter struct {
+	// Path is the path to the executable to run
+	Path string `yaml:"path,omitempty"`
+
+	// Args are the arguments to the executable
+	Args []string `yaml:"args,omitempty"`
+
+	runtimeutil.FunctionFilter
+}
+
+func (c *Filter) Filter(nodes []*yaml.RNode) ([]*yaml.RNode, error) {
+	c.FunctionFilter.Run = c.Run
+	return c.FunctionFilter.Filter(nodes)
+}
+
+func (c *Filter) Run(reader io.Reader, writer io.Writer) error {
+	cmd := exec.Command(c.Path, c.Args...)
+	cmd.Stdin = reader
+	cmd.Stdout = writer
+	return cmd.Run()
+}
diff --git a/kyaml/fn/runtime/exec/exec_test.go b/kyaml/fn/runtime/exec/exec_test.go
new file mode 100644
index 000000000..c878ed993
--- /dev/null
+++ b/kyaml/fn/runtime/exec/exec_test.go
@@ -0,0 +1,112 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package exec_test
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"sigs.k8s.io/kustomize/kyaml/fn/runtime/exec"
+	"sigs.k8s.io/kustomize/kyaml/yaml"
+)
+
+func TestFunctionFilter_Filter(t *testing.T) {
+	var tests = []struct {
+		name           string
+		input          []string
+		functionConfig string
+		expectedOutput []string
+		expectedError  string
+		instance       exec.Filter
+	}{
+		{
+			name: "exec_sed",
+			input: []string{
+				`apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: deployment-foo`,
+				`apiVersion: v1
+kind: Service
+metadata:
+  name: service-foo`,
+			},
+			expectedOutput: []string{
+				`apiVersion: apps/v1
+kind: StatefulSet
+metadata:
+  name: deployment-foo
+  annotations:
+    config.kubernetes.io/path: 'statefulset_deployment-foo.yaml'
+`,
+				`apiVersion: v1
+kind: Service
+metadata:
+  name: service-foo
+  annotations:
+    config.kubernetes.io/path: 'service_service-foo.yaml'
+`,
+			},
+			expectedError: "",
+			instance: exec.Filter{
+				Path: "sed",
+				Args: []string{"s/Deployment/StatefulSet/g"},
+			},
+		},
+	}
+
+	for i := range tests {
+		tt := tests[i]
+		t.Run(tt.name, func(t *testing.T) {
+			// initialize the inputs for the FunctionFilter
+			var inputs []*yaml.RNode
+			for i := range tt.input {
+				node, err := yaml.Parse(tt.input[i])
+				if !assert.NoError(t, err) {
+					t.FailNow()
+				}
+				inputs = append(inputs, node)
+			}
+			if tt.functionConfig != "" {
+				fc, err := yaml.Parse(tt.functionConfig)
+				if !assert.NoError(t, err) {
+					t.FailNow()
+				}
+				tt.instance.FunctionConfig = fc
+			}
+
+			// run the function
+			output, err := tt.instance.Filter(inputs)
+
+			// check for errors
+			if tt.expectedError != "" {
+				if !assert.EqualError(t, err, tt.expectedError) {
+					t.FailNow()
+				}
+				return
+			}
+			if !assert.NoError(t, err) {
+				t.FailNow()
+			}
+
+			// verify the output
+			var actual []string
+			for i := range output {
+				s, err := output[i].String()
+				if !assert.NoError(t, err) {
+					t.FailNow()
+				}
+				actual = append(actual, strings.TrimSpace(s))
+			}
+			var expected []string
+			for i := range tt.expectedOutput {
+				expected = append(expected, strings.TrimSpace(tt.expectedOutput[i]))
+			}
+			if !assert.Equal(t, expected, actual) {
+				t.FailNow()
+			}
+		})
+	}
+}
diff --git a/kyaml/fn/runtime/runtimeutil/example_test.go b/kyaml/fn/runtime/runtimeutil/example_test.go
deleted file mode 100644
index 7b7fa960b..000000000
--- a/kyaml/fn/runtime/runtimeutil/example_test.go
+++ /dev/null
@@ -1 +0,0 @@
-package runtimeutil
diff --git a/kyaml/fn/runtime/runtimeutil/types.go b/kyaml/fn/runtime/runtimeutil/types.go
index fbbb7ad59..5edc4ebc3 100644
--- a/kyaml/fn/runtime/runtimeutil/types.go
+++ b/kyaml/fn/runtime/runtimeutil/types.go
@@ -1,3 +1,6 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package runtimeutil
 
 type DeferFailureFunction interface {