diff --git a/runner/healthcheck.go b/runner/healthcheck.go
index ef79db7..42b63c0 100644
--- a/runner/healthcheck.go
+++ b/runner/healthcheck.go
@@ -14,11 +14,11 @@ func DoHealthCheck(options *Options, flagSet *goflags.FlagSet) string {
 	// RW permissions on config file
 	cfgFilePath, _ := flagSet.GetConfigFilePath()
 	var test strings.Builder
-	test.WriteString(fmt.Sprintf("Version: %s\n", Version))
-	test.WriteString(fmt.Sprintf("Operative System: %s\n", runtime.GOOS))
-	test.WriteString(fmt.Sprintf("Architecture: %s\n", runtime.GOARCH))
-	test.WriteString(fmt.Sprintf("Go Version: %s\n", runtime.Version()))
-	test.WriteString(fmt.Sprintf("Compiler: %s\n", runtime.Compiler))
+	fmt.Fprintf(&test, "Version: %s\n", Version)
+	fmt.Fprintf(&test, "Operative System: %s\n", runtime.GOOS)
+	fmt.Fprintf(&test, "Architecture: %s\n", runtime.GOARCH)
+	fmt.Fprintf(&test, "Go Version: %s\n", runtime.Version())
+	fmt.Fprintf(&test, "Compiler: %s\n", runtime.Compiler)
 
 	var testResult string
 	ok, err := fileutil.IsReadable(cfgFilePath)
@@ -30,7 +30,7 @@ func DoHealthCheck(options *Options, flagSet *goflags.FlagSet) string {
 	if err != nil {
 		testResult += fmt.Sprintf(" (%s)", err)
 	}
-	test.WriteString(fmt.Sprintf("Config file \"%s\" Read => %s\n", cfgFilePath, testResult))
+	fmt.Fprintf(&test, "Config file \"%s\" Read => %s\n", cfgFilePath, testResult)
 	ok, err = fileutil.IsWriteable(cfgFilePath)
 	if ok {
 		testResult = "Ok"
@@ -40,7 +40,7 @@ func DoHealthCheck(options *Options, flagSet *goflags.FlagSet) string {
 	if err != nil {
 		testResult += fmt.Sprintf(" (%s)", err)
 	}
-	test.WriteString(fmt.Sprintf("Config file \"%s\" Write => %s\n", cfgFilePath, testResult))
+	fmt.Fprintf(&test, "Config file \"%s\" Write => %s\n", cfgFilePath, testResult)
 	c4, err := net.Dial("tcp4", "scanme.sh:80")
 	if err == nil && c4 != nil {
 		_ = c4.Close()
@@ -49,7 +49,7 @@ func DoHealthCheck(options *Options, flagSet *goflags.FlagSet) string {
 	if err != nil {
 		testResult = fmt.Sprintf("Ko (%s)", err)
 	}
-	test.WriteString(fmt.Sprintf("IPv4 connectivity to scanme.sh:80 => %s\n", testResult))
+	fmt.Fprintf(&test, "IPv4 connectivity to scanme.sh:80 => %s\n", testResult)
 	c6, err := net.Dial("tcp6", "scanme.sh:80")
 	if err == nil && c6 != nil {
 		_ = c6.Close()
@@ -58,7 +58,7 @@ func DoHealthCheck(options *Options, flagSet *goflags.FlagSet) string {
 	if err != nil {
 		testResult = fmt.Sprintf("Ko (%s)", err)
 	}
-	test.WriteString(fmt.Sprintf("IPv6 connectivity to scanme.sh:80 => %s\n", testResult))
+	fmt.Fprintf(&test, "IPv6 connectivity to scanme.sh:80 => %s\n", testResult)
 
 	return test.String()
 }