diff --git a/src/cmd/tools/dtest/docker/harness/resources/harness.go b/src/cmd/tools/dtest/docker/harness/resources/harness.go
index db316a2517..8c89688a32 100644
--- a/src/cmd/tools/dtest/docker/harness/resources/harness.go
+++ b/src/cmd/tools/dtest/docker/harness/resources/harness.go
@@ -66,8 +66,8 @@ type dockerResources struct {
 // single DB node.
 func SetupSingleM3DBNode(opts ...SetupOptions) (DockerResources, error) {
 	options := setupOptions{}
-	for _, o := range opts {
-		o.apply(&options)
+	for _, f := range opts {
+		f(&options)
 	}
 
 	pool, err := dockertest.NewPool("")
diff --git a/src/cmd/tools/dtest/docker/harness/resources/options.go b/src/cmd/tools/dtest/docker/harness/resources/options.go
index 8dab4aecf0..aa1ab92da1 100644
--- a/src/cmd/tools/dtest/docker/harness/resources/options.go
+++ b/src/cmd/tools/dtest/docker/harness/resources/options.go
@@ -30,30 +30,19 @@ type setupOptions struct {
 	coordinatorImage dockerImage
 }
 
-type SetupOptions interface {
-	apply(*setupOptions)
-}
-
-type dbnodeImageNameOption struct {
-	dockerImage
-}
-
-func (o dbnodeImageNameOption) apply(opts *setupOptions) {
-	opts.dbNodeImage = o.dockerImage
-}
+// SetupOptions is used for passing docker test setup parameters
+type SetupOptions func(*setupOptions)
 
+// WithDBNodeImage sets the name and tag of m3dbnode docker image to be used
 func WithDBNodeImage(name, tag string) SetupOptions {
-	return dbnodeImageNameOption{dockerImage{name, tag}}
-}
-
-type coordinatorImageNameOption struct {
-	dockerImage
-}
-
-func (o coordinatorImageNameOption) apply(opts *setupOptions) {
-	opts.coordinatorImage = o.dockerImage
+	return func(o *setupOptions) {
+		o.dbNodeImage = dockerImage{name, tag}
+	}
 }
 
+// WithCoordinatorImage sets the name and tag of m3coordinator docker image to be used
 func WithCoordinatorImage(name, tag string) SetupOptions {
-	return coordinatorImageNameOption{dockerImage{name, tag}}
+	return func(o *setupOptions) {
+		o.coordinatorImage = dockerImage{name, tag}
+	}
 }