diff --git a/cmd/Chapter07/Exercise07.03/main_test.go b/cmd/Chapter07/Exercise07.03/main_test.go
index 04d3170..faa2410 100644
--- a/cmd/Chapter07/Exercise07.03/main_test.go
+++ b/cmd/Chapter07/Exercise07.03/main_test.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"log"
 	"testing"
 )
 
@@ -36,7 +37,10 @@ func TestNewRecord(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			got := newRecord(tc.inputKey, tc.inputInterface)
 			if got.key != tc.wanted.key {
-				fmt.Errorf("Got: %v wanted %v", got, tc.wanted.key)
+				err := fmt.Errorf("Got: %v wanted %v", got, tc.wanted.key)
+				if err != nil {
+					log.Fatal(err)
+				}
 
 			}
 		})
diff --git a/cmd/Chapter15/Activity15.02/a15.02.go b/cmd/Chapter15/Activity15.02/a15.02.go
index cafe5cd..340e27d 100644
--- a/cmd/Chapter15/Activity15.02/a15.02.go
+++ b/cmd/Chapter15/Activity15.02/a15.02.go
@@ -19,7 +19,11 @@ func (h *PageWithCounter) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(400)
 		return
 	}
-	w.Write([]byte(bts))
+	_, err = w.Write([]byte(bts))
+	if err != nil {
+		log.Fatal(err)
+	}
+
 }
 
 func main() {
diff --git a/cmd/Chapter15/Activity15.03/main.go b/cmd/Chapter15/Activity15.03/a15.03.go
similarity index 84%
rename from cmd/Chapter15/Activity15.03/main.go
rename to cmd/Chapter15/Activity15.03/a15.03.go
index 6bb8dd6..ffffe47 100644
--- a/cmd/Chapter15/Activity15.03/main.go
+++ b/cmd/Chapter15/Activity15.03/a15.03.go
@@ -20,17 +20,19 @@ func (h Hello) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 	cust := Visitor{}
 
-
 	name, ok := vl["name"]
 	if ok {
 		cust.Name = strings.Join(name, ",")
 	}
 
-	h.tpl.Execute(w, cust)
+	err := h.tpl.Execute(w, cust)
+	if err != nil {
+		log.Fatal(err)
+	}
 }
 
 // NewHello returns a new Hello handler
-func NewHello(tplPath string) (*Hello, error){
+func NewHello(tplPath string) (*Hello, error) {
 	tmpl, err := template.ParseFiles(tplPath)
 	if err != nil {
 		return nil, err
@@ -46,4 +48,4 @@ func main() {
 	http.Handle("/", hello)
 
 	log.Fatal(http.ListenAndServe(":8080", nil))
-}
\ No newline at end of file
+}
diff --git a/cmd/Chapter15/Activity15.03/main_test.go b/cmd/Chapter15/Activity15.03/a15.03_test.go
similarity index 62%
rename from cmd/Chapter15/Activity15.03/main_test.go
rename to cmd/Chapter15/Activity15.03/a15.03_test.go
index 88da0ec..bf63ad5 100644
--- a/cmd/Chapter15/Activity15.03/main_test.go
+++ b/cmd/Chapter15/Activity15.03/a15.03_test.go
@@ -1,10 +1,14 @@
 package main
+
 import (
-	"io/ioutil"
+	"io"
+	"log"
 	"net/http"
 	"net/http/httptest"
+	"os"
 	"testing"
 )
+
 func Test_name(t *testing.T) {
 	hdl, err := NewHello("./index.html")
 	if err != nil {
@@ -15,14 +19,17 @@ func Test_name(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	expected, err := ioutil.ReadFile("./teststatics/john.html")
+	expected, err := os.ReadFile("./teststatics/john.html")
 	if err != nil {
 		t.Error(err)
 	}
 	actual := make([]byte, rsp.ContentLength)
-	rsp.Body.Read(actual)
-	if  string(actual)!= string(expected) {
-		t.Errorf("\n%s\n%s", string(expected),string(actual))
+	_, err = rsp.Body.Read(actual)
+	if err != io.EOF {
+		log.Fatal(err)
+	}
+	if string(actual) != string(expected) {
+		t.Errorf("\n%s\n%s", string(expected), string(actual))
 	}
 }
 
@@ -36,13 +43,13 @@ func Test_anonymous(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	expected, err := ioutil.ReadFile("./teststatics/anonymous.html")
+	expected, err := os.ReadFile("./teststatics/anonymous.html")
 	if err != nil {
 		t.Error(err)
 	}
 	actual := make([]byte, rsp.ContentLength)
 	rsp.Body.Read(actual)
-	if  string(actual)!= string(expected) {
-		t.Errorf("\n%s\n%s", string(expected),string(actual))
+	if string(actual) != string(expected) {
+		t.Errorf("\n%s\n%s", string(expected), string(actual))
 	}
-}
\ No newline at end of file
+}