diff --git a/logparser/v5/main.go b/logparser/v5/main.go
index aebd436..c848dd2 100644
--- a/logparser/v5/main.go
+++ b/logparser/v5/main.go
@@ -23,10 +23,14 @@ func main() {
 
 	p := pipe.New(
 		pipe.NewTextLog(os.Stdin),
+		// pipe.NewJSONLog(os.Stdin),
+
 		pipe.NewTextReport(os.Stdout),
 		// pipe.NewJSONReport(os.Stdout),
-		pipe.FilterBy(pipe.DomainExtFilter("com", "io")),
-		pipe.GroupBy(pipe.DomainGrouper),
+
+		// pipe.FilterBy(pipe.DomainExtFilter("com", "io")),
+		// pipe.GroupBy(pipe.DomainGrouper),
+
 		// new(passThrough),
 	)
 
diff --git a/logparser/v5/pipe/group.go b/logparser/v5/pipe/group.go
index 2eda161..e50beca 100644
--- a/logparser/v5/pipe/group.go
+++ b/logparser/v5/pipe/group.go
@@ -17,7 +17,7 @@ type GroupFunc = func(Record) (key string)
 
 // Group records by a key.
 type Group struct {
-	sum  map[string]Record // metrics per group key
+	sum  map[string]record // metrics per group key
 	keys []string          // unique group keys
 	key  GroupFunc
 }
@@ -27,7 +27,7 @@ type Group struct {
 // The returned group will group the record using the key.
 func GroupBy(key GroupFunc) *Group {
 	return &Group{
-		sum: make(map[string]Record),
+		sum: make(map[string]record),
 		key: key,
 	}
 }
@@ -41,7 +41,7 @@ func (g *Group) Consume(records Iterator) error {
 			g.keys = append(g.keys, k)
 		}
 
-		g.sum[k] = r.Sum(g.sum[k])
+		g.sum[k] = r.sum(g.sum[k])
 
 		return nil
 	})
@@ -52,7 +52,7 @@ func (g *Group) Each(yield func(Record) error) error {
 	sort.Strings(g.keys)
 
 	for _, k := range g.keys {
-		if err := yield(g.sum[k]); err != nil {
+		if err := yield(Record{g.sum[k]}); err != nil {
 			return err
 		}
 	}
diff --git a/logparser/v5/pipe/jsonreport.go b/logparser/v5/pipe/jsonreport.go
index f2ada20..26945d5 100644
--- a/logparser/v5/pipe/jsonreport.go
+++ b/logparser/v5/pipe/jsonreport.go
@@ -27,6 +27,6 @@ func (t *JSONReport) Consume(records Iterator) error {
 	enc := json.NewEncoder(t.w)
 
 	return records.Each(func(r Record) error {
-		return enc.Encode(r)
+		return enc.Encode(&r)
 	})
 }
diff --git a/logparser/v5/pipe/record.go b/logparser/v5/pipe/record.go
index 1cd1a6a..33a1119 100644
--- a/logparser/v5/pipe/record.go
+++ b/logparser/v5/pipe/record.go
@@ -18,15 +18,23 @@ type record struct {
 	uniques int
 }
 
-// Sum the numeric fields with another record.
-func (r Record) Sum(other Record) Record {
+// recordJSON is used for marshaling and unmarshaling JSON.
+type recordJSON struct {
+	Domain  string
+	Page    string
+	Visits  int
+	Uniques int
+}
+
+// sum the numeric fields with another record.
+func (r record) sum(other record) record {
 	r.visits += other.visits
 	r.uniques += other.uniques
 	return r
 }
 
-// UnmarshalText to a *Record.
-func (r *Record) UnmarshalText(p []byte) (err error) {
+// UnmarshalText to a *record.
+func (r *record) UnmarshalText(p []byte) (err error) {
 	fields := strings.Fields(string(p))
 	if len(fields) != fieldsLength {
 		return fmt.Errorf("wrong number of fields %q", fields)
@@ -43,23 +51,23 @@ func (r *Record) UnmarshalText(p []byte) (err error) {
 	return validate(*r)
 }
 
-// UnmarshalJSON to a *Record.
-func (r *Record) UnmarshalJSON(data []byte) error {
-	// `methodless` doesn't have any methods including UnmarshalJSON.
-	// This trick prevents the stack-overflow (infinite loop).
-	type methodless Record
+// UnmarshalJSON to a *record.
+func (r *record) UnmarshalJSON(data []byte) error {
+	var rj recordJSON
 
-	var m methodless
-	if err := json.Unmarshal(data, &m); err != nil {
+	if err := json.Unmarshal(data, &rj); err != nil {
 		return err
 	}
 
-	// Cast back to the Record and save.
-	*r = Record(m)
-
+	*r = record{rj.Domain, rj.Page, rj.Visits, rj.Uniques}
 	return validate(*r)
 }
 
+// MarshalJSON of a *record.
+func (r *record) MarshalJSON() ([]byte, error) {
+	return json.Marshal(recordJSON{r.domain, r.page, r.visits, r.uniques})
+}
+
 // parseStr helps UnmarshalText for string to positive int parsing.
 func parseStr(name, v string) (int, error) {
 	n, err := strconv.Atoi(v)
@@ -70,7 +78,7 @@ func parseStr(name, v string) (int, error) {
 }
 
 // validate whether a parsed record is valid or not.
-func validate(r Record) (err error) {
+func validate(r record) (err error) {
 	switch {
 	case r.domain == "":
 		err = errors.New("record.domain cannot be empty")
diff --git a/logparser/v5/pipe/textreport.go b/logparser/v5/pipe/textreport.go
index 0c8c0f0..00ca37e 100644
--- a/logparser/v5/pipe/textreport.go
+++ b/logparser/v5/pipe/textreport.go
@@ -39,10 +39,10 @@ func (t *TextReport) Consume(records Iterator) error {
 	write(w, "DOMAINS\tPAGES\tVISITS\tUNIQUES\n")
 	write(w, "-------\t-----\t------\t-------\n")
 
-	var total Record
+	var total record
 
 	err := records.Each(func(r Record) error {
-		total = r.Sum(total)
+		total = r.sum(total)
 
 		write(w, "%s\t%s\t%d\t%d\n",
 			r.domain, r.page,